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Full text of "Lessons on shells, as given to children between the ages of eight and ten, in a Pestalozzian school, at Cheam, Surrey"

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Quin  ipsis  doctoribus  hoc  esse  curae  velim,  ut  teneras  adhuc 
mentes  more  nutricum  mollius  alant,  et  satiari  veluti  quodam 
jucundioris  disciplinae  lacte  patiantur.  Erit  illud  plenius  interim 
corpus,  quod  mox  adulta  setas  adstringat.  Hinc  spes  roboris. 


'  LESSONS  on  Shells  '  may  be  considered  as  a 
continuation  of  '  Lessons  on  Objects  ;  9  the 
principles  of  teaching  illustrated  in  that  little 
work  are  here  applied  to  an  important  and  inter- 
esting branch  of  Natural  History.  It  is,  like  its 
unpretending  predecessor,  a  transcript  of  the 
actual  labours  of  the  class-room  ;  and  friends 
who  have  visited  the  school,  may  retrace  in  the 
printed  work  the  process  of  which  they  were 
witnesses.  The  end  for  which  it  is  now  laid 
before  the  public  is  not  that  it  may  serve  as  an 
instructive  and  entertaining  volume  to  be  placed 
in  the  hands  of  children;  this  end  is  sufficiently 
attained  by  several  works  of  acknowledged 
merit  ;  which,  in  order  that  the  subject  may  be 
more  familiarly  handled  and  more  vividly  con- 
ceived, represent  an  imaginary  group  of  pupils 


conversing  and  receiving  instruction.  The  ob- 
ject my  sister  has  proposed  to  herself  is  to  place 
a  volume  in  the  Teacher's  hands  which  shall 
help  him  to  re-act  with  his  pupils  the  scenes  that 
are  here  described.  It  is  not  a  drama  offered  for 
perusal  in  the  closet,  but  a  manager's  copy 
commended  to  the  conductors  of  other  theatres 
of  education,  to  enable  their  liliputian  corps 
dramatiques  to  assume  the  same  characters,  play 
the  same  parts,  and  I  will  not  say,  "  fret  their 
little  hour  upon  the  stage,"  but  enjoy  the 
genuine  delight  of  intellectual  activity  judi- 
ciously directed. 

A  want  of  order  and  arrangement  in  the  early 
part  of  '  Lessons  on  Objects/  has  been  alleged  as 
a  blemish  in  that  work  ;  but,  in  point  of  fact,  its 
miscellaneous  character  was  a  studied  feature, 
as  better  suited  to  the  intellectual  state  of  the 
pupils.  Their  first  step  should  be  the  exami- 
nation of  objects  as  nature  presents  them,  or 
rather  as  they  see  them  in  nature,  that  is,  either 
as  insulated  or  as  associated  only  by  accidental 
connection.  When  ideas  are  formed  and  correct 
expressions  familiarized,  the  business  of  classifi- 
cation commences,  the  lessons  assume  a  more 
scientific  character,  and  the  pupils  are  prepared 
to  enter  on  the  province  of  Natural  History. 
The  training,  then,  which  '  Lessons  on  Objects' 
will  have  supplied  for  commencing  '  Lessons 

PREFACE.  vii 

on  Shells,'  will  consist  principally  in  the  im- 
proved faculty  of  observing  natural  features,  in 
the  possession  and  command  of  a  small  voca- 
bulary of  scientific  terms,  in  the  habit  of 
classification,  and  in  tlie  practice  of  giving  a 
written  summary  of  the  knowledge  acquired. 

Several  circumstances  concur  to  recommend 
conchology  as  the  first  branch  of  Natural 
History  to  be  studied  by  younger  pupils. 
Shells  are  of  themselves  interesting,  from  the 
peculiarity  of  their  forms  and  the  variety  of 
their  colours  ;  their  characteristics  are  simple 
and  present  themselves  readily  to  the  eye,  and 
a  variety  of  interesting  information  may  be  given 
respecting  the  animals  which  inhabit  them. 
Added  to  this  the  greater  part  of  the  specimens 
may  be  procured  at  little  expence,  may  be 
easily  preserved,  and  therefore  continually  re- 
produced to  the  class,  and  besides  may,  without 
fear  of  damage,  be  committed  to  the  careless 
hands  of  the  youngest  students. 

It  will  however,  I  know,  be  objected  by 
staunch  anti-reformers  in  education,  that  im- 
prove the  mode  of  teaching  Natural  History 
as  you  will,  you  but  teach  better  that,  which 
had  better  not  be  taught  at  all  ;  for  that 
whatever  abridges  the  time  given  to  classical 
instruction,  weakens  the  nerves  and  sinews  of 
the  mind,  and  but  debases  the  Corinthian 

viii  PREFACE. 

column  of  ancient  lore  by  introducing  the 
barbarous  ornaments  of  modern  science.  My 
answer  is,  we  do  not  propose  to  devote  a  large 
portion  of  time  to  Natural  History  in  ordinary 
cases,  and  even  this  will  be  taken  principally 
during  those  early  years  when  very  little  real 
progress  is  made  in  Greek  or  Latin.  Every  age 
has  its  intellectual,  as  well  as  its  moral  claims  ; 
and  though  the  stern  discipline  of  early  classical 
instruction  may  offer  some  advantages,  still  the 
hours  devoted  to  the  abstractions  of  grammar, 
and  the  puzzling  out  ideas  which  have  no  pro- 
totype in  the  child's  mind  through  the  dark 
mist  of  a  language  little  akin  to  his  maternal 
tongue,  present  very  meagre  food  to  that  under- 
standing they  are  supposed  to  strengthen.  If 
the  child  must  lisp  in  Latin,  let  him  do  so  ;  let 
his  first  Gradus  ad  Parnassum  be  through  the 
quagmires  at  its  base  ;  the  few  choice  spirits 
that  mount  the  summit  may,  perhaps,  tread  it 
with  firmer  step,  and  enjoy  the  prospect  with 
keener  relish  ;  but  that  step  will  riot  be  the  less 
firm,  nor  that  relish  the  less  keen,  because  a 
daily  hour  was  abstracted  for  '  Lessons  on  Ob- 
jects,' or  '  Lessons  on  Shells.'  Not  only  are  the 
sciences  so  linked  together  that  each  gives  each 
a  double  charm,  but  the  faculties  of  the  mind 
are  so  constituted,  as  that  the  vigour  of  each  is 
promoted  by  the  due  developement  of  the  rest. 


And  there  is  a  harmony  as  truly  existing  in  a 
properly  educated  mind,  as  in  a  well- formed 
and  well-exercised  body,  though  the  harmony 
of  the  former  may  not  be  so  easily  discerned  as 
that  of  the  latter.  ;•' 

As  years  advance,  the  study  of  Natural  His- 
tory may  be  confined  to  those  who  manifest  a 
peculiar  taste  for  it,  or  who  exhibit  little  dispo- 
sition for  classical  pursuits.  For,  as  every  age 
has  its  intellectual  claims,  so  also  has  every 
grade  of  talent.  The  schools  of  the  highest 
reputation  have  generally  been  conducted  too 
exclusively  to  the  advantage  of  the  superior 
class  of  minds.  The  fine  porcelain  has  been 
beautifully  moulded  and  delicately  pencilled, 
but  the  coarser  clay  has  been  almost  entirely 
neglected.  Yet  many  a  young  man  who  will 
never  shine  in  the  Senate  House  or  the  Schools, 
may  yet  pursue  Natural  History  with  success, 
and  find  in  such  pursuits  improvement  for  his 
mind,  a  refuge  from  ennui,  and  a  substitute  for 
sensual  pleasures.  There  is  much  truth  as  well 
as  benevolence  in  a  remark,  I  once  heard  from 
an  amiable  coadjutor  of  Pestalozzi  ;  "  Tout 
terrain  est  bon  si  Ton  sait  le  cultiver." 

Much  of  the  instruction  thus  communicated, 
will  doubtless  fade  from  the  mind  ;  but  not  with 
it  will  pass  away  all  the  benefits  arising  from 
these  studies.  In  after  years  they  may  be  recom- 


menced  with  greater  facility,  in  consequence  of 
the  early  training ;  and  every  incidental  reference 
to  these  subjects,  which  conversation  or  litera- 
ture may  present,  will  be  more  readily  seized, 
and  more  clearly  comprehended.  And  may  it 
not  be  anticipated,  that  through  the  judicious 
introduction  of  these  branches  of  education  into 
our  schools,  the  latent  powers  of  genius  may  be 
kindled,  and  talents  elicited  that  shall  push 
forward  the  limits  of  science,*  and  force  the 
Proteus  nature  to  reveal  still  more  of  her  secret 
truths  ? 

C.  MAYO. 

Cheam,  June  15,  1832. 

*  In  confirmation  of  this  idea  it  may  be  stated,  that  a  very 
ingenious  improvement  of  the  dissecting  microscope,  which  has 
merited  a  reward  from  the  Society  of  Arts,  has  been  invented 
by  a  very  young  person  brought  up  on  these  principles.  I 
have  the  more  unmixed  pleasure  and  honest  pride  in  mention- 
ing this  fact,  as  it  refers  not  to  a  pupil  of  my  own,  but  to  one 
educated  at  Stanmore. 


IT  has  been  objected  to  these  Lessons,  that 
the  children  are  instructed  in  the  system  of  Lin- 
naeus, one  confessedly  imperfect,  instead  of  that 
of  Lamarck,  which  has  been  drawn  out  since  the 
science  has  been  enriched  by  modern  discoveries. 
This  objection  would  be  most  reasonable  if  the 
chief  aim  proposed  in  the  work  had  been  to 
teach  the  science  of  conchology, — but  it  is  in 
fact  simply  what  its  name  imports,  LESSONS  ON 
SHELLS  ;  having  for  its  object,  to  develope 
children's  powers  of  observation,  comparison, 
and  classification :  and  to  cultivate  habits  and 
tastes,  which  may  in  after  life  lead  to  a  more 
correct  and  scientific  study  of  the  subject.  In- 
tellectual power  and  not  knowledge,  being  the 
desideratum,  that  system  should  be  pursued, 
which  the  children  can  work  out ;  and  there  can 
be  no  doubt  that  the  Linnrean  is  the  best  adapted 
for  this  purpose.  The  genera  of  Lamarck  are 
principally  determined  by  the  animal  which  the 
children  could  not,  with  the  exception  of  a  very 


few  instances,  have  the  opportunity  of  examining 
— indeed  many  of  the  shells  composing  his 
genera  are  very  rare,  and  they  could  only  know 
them  by  pictures ;  the  generic  distinctions  also 
are  often  so  minute  that  they  would  elude  the 
observations  of  minds  unpractised  in  scientific 
details.  There  is  on  the  contrary  something  in 
the  simplicity  and  clearness  with  which  the  great 
Swede  seized  and  defined  the  broad  outlines  of 
nature  peculiarly  suited  to  the  capacities  of  the 
young;  and  they  may  be  led  with  very  little 
assistance,  to  group  the  shells  according  to  his 
arrangement,  and  to  draw  out  from  their  own 
observation  the  generic  characters.  Nor  will  an 
acquaintance  with  the  Linnsean  system  be  with- 
out its  value,  when  they  may  desire  to  study  a 
more  perfect  classification  than  his;  they  will 
find  the  task  of  subdividing,  separating,  and 
arranging  very  much  more  easy  than  if  they  had 
to  work  upon  materials  altogether  new  to  them  ; 
— they  will  have  points  established  in  their  minds 
to  which  they  may  compare  and  attach  the  new 
ideas  presented  ;  their  perceptions  will  be  quick- 
ened to  discover  similarities  and  differences ;  and 
they  will  find  many  of  the  difficulties  that  em- 
barrass the  student  at  the  very  threshold  of 
science,  overcome  by  their  previous  lessons. 
Some  again  have  objected  to  the  subject  of  the 
lessons,  as  being  so  much  less  interesting  than 


that  of  plants  or  animals.  This,  however,  is  a 
mistake; — the  well-defined,  and  varied  forms  of 
shells,  their  beautiful  colours  and  markings, 
render  them  particularly  attractive,  and  afford 
better  opportunities  than  any  other  branch  of 
natural  history,  for  calling  into  action  the  per- 
ceptive powers.  They  are  well  suited  to  succeed 
"  Lessons  on  Objects ;  " — the  specimens  may 
be  examined  in  the  same  manner,  and  their  parts 
and  qualities  described,  and  no  other  science 
present  the  same  facilities  of  bringing  before 
children,  and  exercising  them  in,  the  principles  of 
classification.  An  additional  interest  is  given 
to  the  study,  when  the  accordance  of  the  shell 
with  the  habits  of  its  animal  can  be  traced. 

In  drawing  out  '  Lessons  on  Shells,'  the  fol- 
lowing works  have  been  consulted,  and  extracts 
made  from  them. 

Burrows'  Elements  of  Conchology.. 

Turton's  Conchological  Dictionary. 

Turton's  Bivalve  Shells  of  the  British  Isles. 

Mawe's  Conchology. 

Montagu's  Testacea  Britannica. 

Flemming's  Philosophy  of  Zoology. 

Lamark's  Historic  Naturelle   des  animaux   sans 


The  Conchologist's  Companion. 
Shaw's  Nature  displayed. 
Sowerby's  Genera  of  Recent  and  Fossil  Shells. 
Dillwyn's  Descriptive  Catalogue  of  Recent  Shells, 

The  plates  which  illustrate  this  work,  have 
been  drawn  from  specimens  actually  presented 
to  the  class ;  they  are  intended  as  an  assistant  to 
the  teacher,  but  not  as  a  substitute  for  the  shells 
themselves  in  the  instruction  of  pupils. 




Teacher.  Do  you  know  what  these  things 
are  which  I  have  brought  in  as  the  subject  of 
our  lesson  to-day  ? 

Child.     They  are  shells. 

Teacher.  Describe  to  me  what  you  mean  by 
a  shell. 

Child.  Oh,  a  shell  is  that  which  covers  a 

Teacher.  Very  true  ;  a  snail  has  a  shell,  but 
in  saying  this  you  do  not  explain  to  me  the  na- 
ture of  a  shell.  When  you  attempt  to  describe 
anything,  you  should  give  such  an  account  as 
would  instruct  a  person  altogether  ignorant  on 
the  subject.  Try  again,  and  tell  me  what  a 
shell  is. 

Child.     A  shell  is  a  hard  covering  or  house 
belonging  to  animals  resembling  slugs. 

2  LESSON  I. 

Teacher.  Of  what  use  do  you  suppose  shells 
to  be? 

Child.  They  must  be  a  defence  and  protec- 
tion to  the  animals  which  they  cover. 

Teacher.  Yes :  shells  are  the  hard  coverings 
of  certain  animals  called  mollusca,  or  mollusks ; 
a  name  derived  from  mol  Us,  soft ;  and  esca,flesh  ; 
if  you  call  to  mind  the  animals  enclosed  in  these 
cases,  you  will  not  fail  to  observe  how  appli- 
cable this  term  is  to  them.  Give  me  some  exam- 
ple to  prove  that  this  name  is  well  chosen. 

Child.  The  snail  has  a  very  soft  fleshy  body. 

Teacher.  Yes,  arid  the  mollusks  in  this  res- 
pect are  all  alike.  I  have  brought  you  some  to 
examine;  look  at  them  well,  and  try  and  dis- 
cover the  characteristics  which  distinguish  them 
from  other  animals.  Here  are  a  snail,  an  oys- 
ter, a  muscle,  and  a  slug. 

Child.  We  shall  not  be  able  to  say  much 
about  such  animals  as  these,  they  are  so  shape- 
less and  uninteresting  in  their  appearance. 

Teacher.  Do  not  form  so  hasty  a  judgment. 
T  hope  soon  to  convince  you  that  it  is  your  igno- 
rance alone  which  causes  you  to  view  them  with 
indifference.  There  is  not  any  part  of  the 
creation  which  you  can  study,  that  will  not 
repay  you  for  your  labour ;  and  when  you  be- 
come better  acquainted  with  the  different  king- 
doms of  nature,  you  will  experience  an  increased 
pleasure  in  your  walks;  and  objects  that  you  have 
hitherto  passed  heedlessly  by,  will  rivet  your 
attention  by  the  wonders  they  unfold  to  you  ; 


above  all,  my  desire  is  that  you  should  be  led  to 
trace  in  all  that  nature  presents,  the  hand  of  an 
Almighty  and  beneficent  Creator.  When  you 
are  struck  with  the  organization  of  a  plant,  fitting 
it  for  some  particular  purpose,  or  see  the  means 
of  defence  possessed  by  one  animal,  of  attack  by 
another,  should  your  admiration  rest  in  these 
instruments,  whilst  you  forget  Him  who  prepared 
and  fitted  the  instrument  for  its  appointed  work  ? 
Suppose  that  you  have  yourself  made  or  done 
anything  very  nicely  and  with  great  pains  for  a 
friend,  would  you  feel  satisfied,  or  think  it  just, 
if,  whilst  your  performance  was  admired,  you 
were  forgotten  ? 

Child.  I  should  consider  such  conduct  very 

Teacher.  And  what  lesson  do  you  suppose 
that  I  wish  to  teach  you  by  drawing  your  atten- 
tion to  your  own  feelings  when  your  industry 
and  ingenuity  have  been  thus  overlooked  ? 

Child.  That  when  we  are  strnck  with  the 
beauty  and  utility  of  any  of  God's  works,  we 
should  praise  him  for  his  wisdom,  and  thank  him 
for  his  goodness. 

Teacher.  It  is  with  such  feelings  that  I  wish 
you  to  study  Natural  History,  and  it  would  then 
prove  a  very  delightful  and  profitable  employ- 
ment.* You  must  now  return  to  the  consider- 
ation of  the  animals  before  you.  Examine  them 

*  It  is  most  important  in  giving  instruction  in   Natural 
History,  early  to  accustom  children  to  recognise  the  God  of 
nature  in  his  works.    If  God  be  robbed  of  his  glory,  how 
B  2 

4  LESSON  I. 

carefully— exercise  your  different  senses  upon 
them — mark  the  various  parts  of  their  bodies — 
consider  to  what  use  each  part  is  likely  to  be 
destined — and  reflect  upon  what  you  know  of 
their  habits.  By  using  well  your  senses  and  your 
judgment,  you  will  be  able  to  find  out  much  for 
yourselves.  When  you  are  at  the  sea-side,  or 
out  at  sea,  you  may  collect  facts  illustrative  of 
the  history  of  these  animals. 

Child.  That  would  be  exceedingly  interesting, 

Teacher.  Yes  it  would  ;  but  you  need  not 
wait  for  such  "opportunities.  Rivers,  and  even 
the  garden,  will  afford  you  specimens  for  obser- 
vation :  but  what  have  you  now  to  do  ? 

Child.  To  examine  the  animals  before  us,  to 
use  our  senses  upon  them  as  we  did  in  our  lessons 
on  objects,  to  name  their  parts,  and  the  uses  of 
their  parts  as  far  as  we  know  them. 

Teacher.  Yes.  I  wish  you  first  to  observe 
these  creatures  attentively ;  and  that  you  may 
discover  readily  what  is  peculiar  to  them,  you 
must  in  your  own  minds  compare  their  qualities, 

can  we  anticipate  a  blessing  on  our  labours  ?  Has  not  expe- 
rience proved,  that  the  study  of  the  wonders  of  creative 
wisdom  does  not  lead  the  natural  heart  to  the  Creator  ?  Is 
it  not  notorious,  that  amongst  the  followers  of  science  is  con- 
tinually seen  the  practical,  if  not  the  avowed  Atheist.  Let 
this  be  a  beacon  to  the  Christian  instructor,  and  let  it  be  his 
careful  endeavour  to  guard  against  the  fatal  error  of  speaking 
of  God's  works  independently  of  him.  As  we  are  called  upon 
to  walk  by  faith,  and  not  by  sight,  it  is  essential  to  lead  chil- 
dren to  see  God  in  all  things,  and  to  trace  Him  who  is  him- 
self invisible  in  those  outward  manifestations  of  his  power  and 
goodness,  which  are  within  the  reach  of  their  observation. 


parts  and  habits,  with  what  you  know  of  other 
animals.  First,  tell  me  some  qualities  that  appear 
to  you  to  be  common  to  all  the  mollusca. 

Child.  Their  bodies  are  soft,  fleshy,  moist, 
and  cold. 

Teacher.  Yes,  you  remember  their  name  is 
given  to  them  from  their  softness.  Observe 
also  the  action  of  a  snail  when  you  come 
near  to  it. 

Child.  It  draws  its  body  into  its  shell  for 

Teacher.  Yes.  The  bodies  of  the  Mollusca 
are  contractile,  that  is,  have  a  strong  power  of  con- 
traction which  they  exercise  by  means  of  muscles. 
What  more  do  you  remark  in  these  creatures  ? 

Child.  They  have  a  thick  skin  which  appears 
loose  in  some  of  them. 

Teacher.  This  skin  is  called  the  sac  or  man- 
tle ;  and  is  peculiar  to  the  molluscous  tribe.  It 
is  constantly  moistened  by  aslimy  exudation,  and 
is  also  full  of  pores  and  glands,  of  which  I  shall 
have  occasion  to  speak  in  a  future  lesson.  What 
are  pores  ? 

Child.     Pores  are  very  small  holes. 

Teacher.     What  do  you  know  about  glands  ? 

Child.  I  do  not  exactly  know  what  glands 
are  ;  but  we  have  glands  in  our  throats,  are 
those  of  the  mollusks  the  same  as  ours  ? 

Teacher.  They  are  of  the  same  nature,  but 
much  smaller  than  those  in  our  throats.  The 
office  of  glands  is  to  secrete  or  separate  fluids  of 
various  kinds  from  the  general  fluid  of  the  sub- 

6  LESSON  I. 

stance.  Animals  as  well  as  vegetables,  are 
supplied  with  a  greater  number  of  glands ;  the 
tears  of  animals  are  an  example  of  secretion 
formed  by  means  of  such  organs,  so  is  the  honey 
of  plants.  As  the  glands  form  little  reservoirs, 
they  often  appear  like  small  swellings,  percep- 
tible to  the  sight  and  touch.  Now  can  you  tell 
me  what  glands  are  ? 

Child.  They  are  organs  by  which  are  secre- 
ted some  particular  fluid  from  the  general  fluid 
of  the  body. 

Teacher.  To  return  to  the  mantle  ;  it  some- 
times envelops  the  mollusk  like  a  purse,  leaving 
an  opening  only  where  its  mouth  is  situated  ; 
sometimes  it  extends  on  the  two  sides,  forming 
expansions  which  perform  the  part  of  fins. 
Sometimes  it  spreads  over  the  shell  itself,  which 
in  this  case  has  always  a  fine  polish.  Compare, 
as  I  desired  you,  the  mollusk s,  with  other 
animals,  and  tell  me  what  further  peculiarity 
you  discover  in  them. 

Child.  They  have  no  bones,  their  bodies  are 
only  a  mass  of  soft  flesh. 

Teacher.  They  have  certainly  no  bones ;  but 
in  the  mollusks  which  we  purpose  studying, 
the  shell,  by  acting  as  a  support  to  the  body, 
seems  in  some  measure  to  answer  the  purpose  of 
bones.  What  more  do  any  of  you  discover 
in  these  animals  ? 

Child.     They  do  not  appear  to  have  any  blood . 

Teacher.  They  have  not  red  blood  as  we 
have  ;  but  are  they  composed  entirely  of  solid 
matter  ? 


Child.     No,  for  when  a  snail  is  trodden  upon, 
a  white  fluid  issues  from  it ;  is  this  its  blood  ? 

Teacher.  Yes,  it  may  be  considered  as  a  kind 
of  blood.  How  does  it  differ  from  that  which 
circulates  through  our  bodies  ? 
Child.  It  is  white  and  cold. 
Teacher.  True ;  and  in  consequence  some 
naturalists  have  not  considered  it  as  blood,  and 
have  described  the  mollusca  to  be  exsanguin- 
eous  ;  a  term  signifying  without  blood,  and 
derived  from  Latin  ex9  out  of,  and  sanguine, 
blood.  As  this  fluid  flows  through  their  bodie.s 
in  vessels  issuing  from  their  hearts,  it  is  now 
generally  called  their  blood.  What  are  you 
watching  in  the  snail  ? 

Child.  The  very  quick  manner  in  which  it 
draws  in  its  horns,  and  shrinks  into  its  shell,  if 
it  is  touched. 

Teacher.     What  would  you  determine  with 
respect  to  the  animal  from  this  circumstance  ? 
Child.     That  it  has  the  sense  of  feeling. 
Teacher.   Yes ;  and  which  part  appears  most 
sensitive  ? 

Child.     The  horns. 

Teacher.  And  do  you  observe  how  the  little 
animal  feels  about,  and  tries  with  these  projec- 
tions which  you  call  horns  ?  They  have  from 
thence  been  termed  Tentacula9  from  the  Latin, 
tentare,  to  try  or  feel.  How  many  tentacula  have 
snails  ? 

Child.     Four. 

Teacher.     The    tentacuia  vary  in   number  ; 

8  LESSON  I. 

many   mollusks  have  only  two.    The  sense  of 
feeling  resides  in  the  nerves. 

Child.  Oh  !  then  the  mollusks  must  have 

Teacher.  Yes,  they  have  nerves.  Do  you 
perceive  any  other  organs  of  the  senses  besides 
the  tentacula? 

Child.  There  are  black  specks  on  the  horns 
of  the  snail  which  appear  like  eyes. 

Teacher.  These  specks  are  the  organs  of 
sight,  of  which  mollusks  have  never  more  than 
one  pair.  The  sense  of  seeing,  however,  is  not 
universally  possessed  by  this  class  of  animals. 
The  organs  of  hearing  and  smelling  have  never 
been  discovered  in  any  of  them,  but  they  are  sup- 
posed to  possess  the  latter  from  the  readiness 
with  which  they  select  suitable  food.  This  cir- 
cumstance also  proves  that  they  possess  the  sense 
of  taste.  You  must  now  recapitulate  all  that  has 
been  said  concerning  the  mollusca.  Whence  is 
the  name  derived  ? 

Child.     From  mollis,  the  Latin  for  soft. 

Teacher.     What  kind  of  body  have  they  ? 

Child.     Cold,  slimy,  soft,  and  fleshy. 

Teacher.  Yes  ;  and  another  quality  you 
observed  when  I  touched  the  snail  several 

Child.     That  its  body  is  contractile. 

Teacher.  And  what  enabled  it  so  quickly  to 
contract  its  body,  and  retreat  into  its  shelter  ? 

Child.     Its  being  furnished  with  muscles. 

Teacher.     When  you  compare  these  animals 


with  others,    in  what  respect  do   they   appear 
deficient  ? 

Child.  They  have  no  bones,  the  shell  acting 
as  a  support  to  their  bodies,  which  are  attached 
to  it  by  muscles. 

Teacher.     What  envelops  the  mollusca  ? 

Child.     A  sac  or  mantle. 

Teacher.     Describe  the  mantle. 

Child.  The  mantle  is  full  of  pores  and  glands 
and  is  moistened  by  a  slimy  exudation— some- 
times it  quite  encloses  the  animal,  having  only 
one  opening  like  a  purse,  sometimes  it  has  ex- 
pansions at  the  sides,  like  fins,  and  sometimes  it 
spreads  over  the  shell. 

Teacher.     What  are  glands  ? 

Child.  Small  lumps  containing  fluids,  which 
are  separated  from  the  blood. 

Teacher.  Yes,  in  animals  the  glands  secrete 
fluids  from  the  blood ;  but  in  vegetables  from 
the  sap.  Have  these  animals  any  blood  ? 

Child.     Yes ;  but  it  is  white  and  cold. 

Teacher.  In  what  respects  is  it  similar  to  blood  ? 

Child.  It  circulates  through  the  body  in 
vessels  issuing  from  the  heart. 

Teacher.  What  senses  are  enjoyed  by  the 
mollusca  ? 

Child.  The  senses  of  feeling,  seeing,  tasting, 
and,  it  is  supposed  smelling. 

Teacher.  In  what  part  of  their  frames  is  the 
sense  of  feeling  most  acute  ? 

Child.     In  the  tentacula. 

Teacher.  Tell  me  the  derivation  of  that  term  ? 

10  LESSON  I. 

Child.  It  is  derived  from  the  Latin,  Tentare, 
to  try. 

Teacher.  But  what  must  they  possess  in 
order  to  be  able  to  feel  ? 

Child.     Nerves. 

Teacher.  I  will  now  read  to  you  a  summary 
of  your  lesson,  and  I  shall  expect  you  afterwards 
to  write  it  from  recollection. 

Teacher.  The  mollsuca  have  soft,  slimy,  cold, 
fleshy,  and  contractile  bodies.  They  have 
no  bones,  but  their  shell  acts  as  a  support  to 
their  frame.  They  have  muscles  by  which 
they  are  attached  to  their  shells,  and  by  which 
they  move  their  bodies.  They  are  enclosed  in  a 
skin  called  the  mantle,  or  sac,  which  is  full  of 
pores  and  glands.  Sometimes  the  animal  is  so 
completely  enveloped  in  this,  as  only  to  present 
an  opening  where  the  mouth  is  situated,  some- 
times it  spreads  over  the  shell,  and  sometimes  it 
has  external  expansions  answering  the  purpose 
of  fins.  The  mollusca  have  not  warm  red  blood, 
but  a  white  cold  fluid  issues  from  their  hearts 
and  circulates  through  their  frames.  They 
have  nerves,  and  consequently,  feeling ;  and  this 
sense  seems  most  accute  in  their  tentacula.  Some 
have  eyes,  but  others  do  not  enjoy  the  sense  of 
sight.  They  appear  to  have  the  power  of  smel- 
ling and  tasting,  but  no  traces  of  ears  have  been 

*  This  little  summary  of  the  substance  of  the  lesson  may 
be  read  over  twice  to  the  children,  and  they  should  then  be 



(  To  commence  with  a  repetition  of  the  summary  of  the  former 

Teacher.  Examine  these  animals  again,  com- 
pare them  with  insects,  and  tell  me  if  you 
observe  any  deficiency  in  their  construction. 

Child.     They  have  not  any  limbs. 

Teacher.  Very  true.  They  have  not  limbs 
or  joints,  as  insects,  nor  are  they  divided,  or 
moved  by  means  of  rings,  as  worms. 

Child.     Yet  they  move  about. 

Teacher.  Yes ;  the  greater  number  of 
mollusks  have  the  power  of  locomotion,  that  is, 
of  moving  from  place  to  place ;  the  term  is  de- 
rived from  the  Latin  locus,  a  place.  We  will 

required  to  write  it  as  well  as  they  can  from  recollection.  It 
would  be  desirable  also  that  they  should  repeat  it  at  the  com- 
mencement of  the  succeeding  lesson.  This  process  may  appear 
tedious,  but  the  result  will  be  most  satisfactory  both  to  the 
teacher  and  pupils.  The  latter  should  acquire  so  clear  a  know- 
ledge of  the  facts  brought  before  them,  and  have  them  so  well 
imprinted  on  their  minds,  that  they  may,  through  all  their 
progress,  be  enabled  without  confusion  or  hesitation,  to  recur 
to  each  preceding  step.  Their  information  should  be  like  a 
chain,  which  is  held  unbroken  in  the  grasp ;  and  when  this  is 
accomplished,  a  power  of  mind  is  elicited  which,,  independently 
of  the  knowledge  obtained,  will  prove  most  valuable  when 
applied  to  more  important  subjects. 

12  LESSON  II. 

first  examine  the  organs  by  means  of  which  this 
power  is  exercised.  In  what  manner  do  snails 
and  slugs  make  their  way  along  the  ground  ? 

Child.  Their  skin  expands  at  the  sides  of  the 
body,  and  adheres  to  the  earth,  and  then  they 
draw  themselves  on. 

Teacher.  This  fleshy  expansion  under  their 
bodies  is  full  of  muscles,  which  they  dilate  and 
contract  at  pleasure.  It  adheres  like  a  sucker, 
and  the  animal  advances  by  fixing  the  fore  part 
to  the  ground  and  drawing  the  remainder  after 
it.  This  instrument  is  called  a  foot.  In  some 
species,  as  the  snail,  it  is  attached  to  the  under 
part  of  the  body  by  its  whole  length,  but  in 
others  it  is  free  at  one  end,  and  can  be  extended 
or  drawn  in  at  pleasure.  When  it  is  free  it  is 
called  a  leg,  and  is  generally  tongue-shaped ;  it 
is  frequently  used  as  an  organ  of  motion,  but 
sometimes  the  animal  employs  it  as  a  paw  for 
digging  holes  in  the  sand  or  mud.  But  do  you 
think  that  this  organ  will  enable  the  mollusks  to 
advance  in  all  the  situations  in  which  they  are 
placed  ? 

Child.  No,  not  when  they  are  in  the  water ; 
then  they  must  swim. 

Teacher.  Yes,  and  this  action  is  performed 
either  by  the  serpentine  movements  of  the  foot 
and  body,  or  by  the  movement  of  expanded 
portions  of  the  skin  or  tentacula,  which  forces 
them  onwards  in  the  same  manner  as  oars  pro- 
pel a  boat. 

Child.     Have  all  the  mollusks  that  live  in 


the  water  either  tentacula  or  expansions  of  the 

Teacher.  No  ;  some  have  no  such  elongated 
parts.  I  think  you  might  have  discovered  this 
yourselves  by  observing  one  of  the  animals 
before  you. 

Child.  Oh  yes,  the  oyster.  Such  mollusks 
cannot  move  then. 

Teacher.  That  is  not  true  of  all,  some  are 
immoveably  attached  to  the  spot  where  they 
first  received  life  ;  but  others  have  the  power  of 
leaping  or  shifting  their  positions  with  a  sudden 
jerk,  produced  by  rapidly  shutting  the  two 
pieces  of  their  shells  ;  others  again  transport 
themselves  from  one  spot  to  another  by  the  force 
with  which  they  draw  in  and  eject  the  fluid  in 
which  they  live.  Many  species  are  furnished 
with  a  kind  of  bladder  by  inflating  or  contract- 
ing which  they  can  rise  or  sink  in  the  water  as 
circumstances  require.  Try  and  enumerate  the 
various  means  of  locomotion  possessed  by  the 

Child.  Many  creep  by  means  of  a  fleshy 
elongation,  which  is  in  some  a  foot,  in  others  a 
leg.  In  the  water  they  swim,  making  their  way 
either  by  the  serpentine  movement  of  their 
bodies,  or  by  the  use  of  tentacula.  Some  can 
rise  and  sink  in  the  sea,  and  some  make  a  leap 
by  rapidly  closing  their  shells,  or  by  drawing  in 
water  and  suddenly  forcing  it  out  again. 

Teacher.  When  we  study  the  different  kinds 
of  mollusca,  I  shall  speak  to  you  more  fully  of 


their  peculiar  habits.  Did  you  ever  observe 
when  you  have  been  on  the  sea-coast,  numerous 
shells  clustered  together  on  the  rocks  and  stones  ? 

Child.  Yes,  barnacles  ;  are  they  the  animals 
which  never  move  from  the  spot  to  which  they 
are  attached  ? 

Teacher.  Yes,  the  barnacles  and  many  other 
mollusks  live  and  die  on  the  spot  where  their 
existence  first  commenced. 

Child.     How  are  they  fixed  to  the  spot  ? 

Teacher.  Some  of  them,  as  the  barnacles, 
are  cemented  to  the  rocks  by  the  same  sub- 
stance of  which  their  shells  are  formed  ;  others 
have  a  less  permanent  mode  of  adhesion,  and 
fasten  themselves  by  means  of  a  viscid  liquid 
which  they  discharge  from  glands  in  their  bodies ; 
some  produce  silky  filaments,  one  extremity  of 
which  remains  in  connexion  with  themselves, 
while  the  other  is  fixed  to  marine  substances, 
and  thus  anchoring  themselves,  they  float  secure 
in  the  ocean.  The  bundle  of  filaments  which 
the  animal  draws  from  his  body  for  this  purpose 
is  called  a  byssus.*  Do  you  know  any  other 
shells  that  are  with  difficulty  removed  from  the 
rocks  ? 

Child.     Yes,  the  limpet. 

Teacher.     The  manner  in  which  this  mollusk 

*  The  children  should  see  and  examine  for  themselves  these 
contrivances.  A  pinna  with  its  byssus,  and  barnacles  on  a 
stone  are  easily  procured.  The  web  of  the  spider  would  give 
them  a  good  idea  of  the  work  of  the  pinna,  being  produced  in 
a  very  similar  manner. 


fixes  itself  upon  the  rocks,  is  very  simple, 
though  very  curious.  It  forms  within  its 
shell,  a  vacuum,  that  is,  a  space  free  from  air, 
derived  from  Latin,  vacuws,  empty.  By  filling  up 
the  hollow  of  the  shell  with  the  fleshy  substance 
of  its  body,  it  expels  the  air,  and  having  fastened 
its  body  to  the  rock  by  a  viscid  substance,  con- 
tracts itself  in  the  centre,  thus  leaving  a  space 
within  the  shell  entirely  free  from  air.  As  there 
then  is  no  internal  expansion  of  this  fluid, 
the  pressure  of  the  external  atmosphere  meets 
with  no  resistance,  and  in  consequence  acts  with 
so  much  force  upon  the  shell,  that  it  cannot  be 
removed  from  its  situation  without  great  effort. 
Repeat  to  me  now  the  different  means  of  attach- 
ment used  by  the  mollusca. 

Child.  Some  fix  themselves  by  silky  fila- 
ments called  a  byssus,  some  by  a  viscid  cement, 
others  by  forming  a  vacuum,  and  others  attach 
themselves  to  the  rocks  by  the  same  substance 
of  which  their  shells  are  made. 

Teacher.  The  shells  which  by  any  of  these 
means  are  rendered  stationary,  are  called  fixed 
shells,  the  others  free  shells.  Does  anything 
strike  you  with  regard  to  these  two  kinds  of 
mollusca  ? 

Child.  The  inhabitants  of  the  fixed  shells 
must  be  badly  off.  They  cannot  procure  nour- 

Teacher.  They  cannot  indeed  go  in  search 
of  it,  but  the  continued  motion  of  the  waves,  or 
the  flowing  of  the  tide  brings  a  fresh  supply  of 

16  LESSON  II. 

water  swarming  with  the  little  animals  upon 
which  they  subsist,  and  some  increase  the  rapi- 
dity of  this  supply,  by  forming  currents  in  the  sea. 

Child.  What  very  clever  contrivers  these 
animals  seem  to  be. 

Teacher.  Yes,  and  your  remark  leads  me  to 
an  important  consideration,  to  which  I  wish  to 
direct  your  attention.  How  do  these  little  ani- 
mals know  that  it  is  well  for  them  to  attach 
themselves  to  other  substances.  How  have  they 
learnt  to  form  the  vacuum,  or  weave  the  silken 
filaments  ? 

Child.     Is  it  riot  instinct  that  directs  them  1 

Teacher.  Yes,  but  can  you  tell  me  what 
instinct  is  ? 

Child.     It  is  something  that  guides  animals. 

Teacher.     Is  man  taught  in  the  same  way  ? 

Child.  No,  we  have  reason,  and  can  think 
about  what  we  do. 

Teacher.  Well,  let  us  consider  a  little  the 
difference  between  that  which  directs  man,  and 
that  which  guides  other  animals.  Suppose  a 
child  were  to  see  a  fire  for  the  first  time :  not 
knowing  its  nature,  he  might  perhaps  put  his 
finger  into  it.  Would  he  do  so,  do  you  think, 
a  second  time  ? 

Child.  No,  he  would  recollect  the  conse- 
quences of  having  done  so  before. 

Teacher  He  would  have  learnt  then  from  his 
own  experience  :  but  is  all  knowledge  obtained 
by  our  own  experience ;  do  you  not  know  any 
thing  but  what  you  have  discovered  yourself  ? 


Child,    We  learn  from  the  accounts  of  others. 

Teacher.  True,  we  are  instructed  by  the 
experience  of  others.  But  watch  any  animal,  a 
bee  for  instance  :  when  it  makes  its  cell,  does 
it  try  several  times  before  he  succeeds  ? 

Child.  No,  he  does  it  perfectly  at  the  first 

Teacher.  Has  it  been  taught  by  its  own 
species  ? 

Child.     No. 

Teacher.  What  then  is  the  difference  between 
the  principle  that  guides  the  bee,  and  that  which 
guides  man  ? 

Child.  Man  is  taught  both  by  his  own  ex- 
perience, and  that  of  others  ;  but  the  bee  acts 
rightly  without  either. 

Teacher.  Yes ;  it  is  directed  immediately 
by  a  principle  implanted  in  it  by  the  Creator. 
This  principle  is  called  instinct,  and  is  well 
defined  to  be  prior  to  experience,  and  indepen- 
dant  of  instruction.  I  will  now  read  to  you  the 
summary  of  to-day's  lesson — attend,  that  you 
may  be  able  to  write  an  account  of  it  from 

Many  of  the  mollusca,  though  destitute  of 
jointed  limbs,  have  organs  of  motion ;  some 
have  a  fleshy  expansion  extending  the  length  of 
the  body,  called  a  foot  ;  this  is  full  of  muscles, 
by  which  it  is  moved,  it  acts  like  a  sucker,  and 
the  animal  advances  by  fixing  the  fore  part  to 

18  LESSON  II. 

the  ground,  and  drawing  the  remainder  after  it. 
This  organ  is  sometimes  free,  and  can  be  ex- 
tended or  contracted  at  pleasure ;  it  is  then 
called  a  leg,  and  is  used  either  as  an  organ  of 
motion,  or  as  a  paw  for  digging  holes  in  the 
sand  or  mud.  In  the  water,  some  mollusca 
advance  by  means  of  the  serpentine  motion 
of  their  bodies,  others  by  the  movement  of  either 
expanded  portion  of  the  skin  or  tentacula. 
Some,  quite  destitute  of  any  separate  organs  of 
motion,  effect  a  change  in  their  position  by 
ingenious  contrivances ;  thus,  the  common  scal- 
lops, by  rapidly  shutting  the  two  pieces  of 
their  shell,  can  transport  themselves  a  short 
distance  ;  and  others  send  themselves  forward 
by  drawing  in  water  and  ejecting  it  again  with 
great  force.  Many  species  are  furnished  with  a 
kind  of  air  bladder,  by  inflating  or  contracting 
which,  they  rise  and  sink  in  the  water  as  cir- 
cumstances may  require.  Some,  however,  have 
no  power  at  all  of  moving,  but  remain  fixed 
through  life  to  the  spot  where  they  commenced 
their  existence.  Their  modes  of  attachment 
vary  ;  some  firmly  fix  themselves  by  the  same 
materials  of  which  they  make  their  shells : 
others  glue  themselves  by  a  viscid  cement  drawn 
from  glands  in  their  bodies ;  and, others  throw 
out  a  byssus,  and  anchor  themselves  securely  to 
some  rock.  The  limpet,  by  forming  a  vacuum 
in  his  shell  maintains  a  firm  hold  of  marine  sub- 
stances. The  shells  thus  rendered  stationary, 
are  called  fixed  shells,  whilst  those  inhabited  by 
animals  that  move  about,  are  termed  free  shells. 



Teacher.  What  organs  in  the  mollusca  have 
we  considered  ? 

Child.     The  organs  of  sense  and  of  motion. 

Teacher,  And  what  other  organs  are  essential 
to  animal  existence  ? 

Child.  All  animals  must  have  organs  by 
which  they  feed  themselves. 

Teacher.  Have  you  ever  observed  snails 
eating  ? 

Child.  Yes ;  I  have  seen  them  devour  a  leaf, 
and  I  should  think  they  must  have  teeth. 

Teacher.  They  have  two  jaws  which  are  fur- 
nished with  small  teeth,  fitted  for  cutting  vege- 
table substances. 

Child.  Have  all  the  mollusca  mouths  like 
that  of  the  snail  ? 

Teacher.  No,  the  mouths  of  the  different 
species,  as  well  as  their  other  organs,  are  adapted 
to  the  peculiar  wants  and  habits  of  the  animals. 
Some  have  only  a  simple  opening  to  receive  the 
little  animalcula  brought  to  them  by  the  waves, 
and  which  do  not  require  mastication.*  Most  of 
those  which  live  upon  the  produce  of  the  vege- 
table kingdom  have  a  muzzle  with  jaws  which 
are  either  horny  or  armed  with  teeth,  f  The 

*  The  Oyster.  t  The  snail. 

C  2 


carnivorous  *  mollusca  have  usually  a  kind  of 
proboscis  ;  this  instrument  is  a  fleshy  pliable  tube 
terminated  by  a  round  aperture,  with  a  cartilagi- 
nous edge  armed  with  little  teeth. f  The  proboscis 
is  supplied  with  muscles,  by  means  of  which 
the  animal  can  protrude  or  draw  it  in  at  pleasure; 
many  use  it  to  pierce  other  shells,  that  they  may 
suck  out  the  flesh  of  the  inhabitant.  I  have 
mentioned  to  you  three  different  kinds  of  mouths 
which  mollusks  are  found  to  possess  ;  describe 
them  to  me. 

Child.  Some  have  only  a  simple  opening, 
others  have  jaws,  either  of  a  horny  substance, 
or  armed  with  teeth ;  and  others  possess  a  plia- 
ble fleshy  proboscis,  moved  by  muscles,  and  ter- 
minated by  a  cartilaginous  ring  which  has  teeth. 

Teacher.  Which  are  the  feeders  upon  vege- 
tables, and  which  upon  animals,? 

Child.  The  mollusks  which  have  a  muzzle 
feed  upon  vegetables,  those  with  a  proboscis  are 

Teacher.  In  feeding  there  is  another  point  to 
be  considered,  how  the  food  is  to  be  brought  to 
the  mouth.  How  do  we  manage  this  operation  ? 

Child.     By  means  of  our  hands  ? 

Teacher.  And  what  makes  it  particularly 
needful  that  man  should  possess  hands  ? 

Child.     His  erect  position. 

Teacher.  You  have  often  had  an  opportunity 
of  watching  some  of  the  mollusks  which  are 

*  From  the  Latin  carne,  flesh,  and  voro,  I  eat. 
t  Voluta  tnusica. 


vegetable  feeders,  you  can  tell  me  how  they 

Child.  The  snail  feeds  upon  vegetables,  it 
crawls  upon  its  fleshy  foot  till  it  reaches  a  plant, 
and  then  gnaws  it  with  its  jaws. 

Teacher.  The  animal  feeders  stretch  out 
their  proboscis  and  catch  hold  of  their  prey,  and 
some  grasp  it  with  their  tentacula,  and  thus 
bring  it  within  reach  of  their  mouths.  Those 
mollusks  which  have  only  an  opening,  have  a 
supply  of  food  brought  to  them  by  the  continued 
movement  of  the  waves  and  the  flowing  of  the 
tides,  and  you  must  remember  my  telling  you 
of  some  who  ingeniously  increase  this  supply  by 
creating  an  eddy  in  the  water.  I  have  brought 
you  an  oyster  and  a  snail,  and  wish  you  to  com- 
pare them  together,  and  tell  me  what  appears  to 
you  to  be  the  most  striking  difference  between 
the  two. 

Child.  The  snail  has  a  head,  but  the  oyster 
is  only  as  oft  lump  of  flesh,  and  has  no  appear- 
ance of  a  head. 

Teacher.  Many  of  the  mollusks  like  the 
oyster,  have  no  obviously  distinct  head.  This 
circumstance  has  led  naturalists  to  divide  these 
animals  into  two  great  classes.  How  should 
you  think  they  are  distinguished  ? 

Child.  One  class  contains  those  mollusks 
which  have  heads ;  the  other,  those  which  are 
destitute  of  heads. 

Teacher.  The  former  are  called  mollusca 
cephala  from  the  Greek  /ce^aX»j  (kephale)  a  head; 
the  latter,  mollusca  acephala  from  the  Greek 


a  without,  and  K€<paXy  a  head.  The  mollusca 
acephala  have  not  a  distinct  head,  nor  any  ap- 
pearance of  the  organs  of  sight  or  hearing,  their 
mouth  is  only  a  simple  opening,  and  their  organi- 
zation altogether  is  much  more  simple  than  that 
of  the  mollusca  cephala.  They  are  aquatic  ani- 
mals, and  their  shell  is  composed  of  two  pieces,  to 
which  they  are  attached  by  muscles.  Which  of 
these  mollusks  would  you  place  in  this  class  ? 

Child.  The  oyster,  the  scollop,  and  the 

Teacher.  Here  is  the  summary  of  to-day's 
lesson; — read  it  carefully,  and  then  take  pains 
to  write  me  a  correct  account  of  it. 

The  organs  of  nutrition  possessed  by  the 
mollusca,  vary  according  to  their  habits.  Those 
which  feed  on  vegetables,  have  a  muzzle  com- 
posed of  horny  jaws  sometimes  armed  with 
teeth.  Many  of  the  carnivorous  mollusca,  have 
a  fleshy,  pliable  proboscis,  moved  by  muscles, 
and  terminated  by  a  cartilaginous  border,  fur- 
nished with  teeth  ;  others  have  only  a  simple 
opening,  and  possess  no  organ  of  mastication. 
The  mollusca  are  divided  into  two  great  classes  ; 
one  contains  those  animals  possessing  a  head, 
which  are  called  mollusca  cephala,  the  other 
contains  those  which  are  destitute  of  a  head, 
and  are  called  mollusca  acephala.  The  latter 
are  distinguished  by  a  much  more  simple  organi- 
zation, live  invariably  in  water,  and  inhabit 
shells  composed  of  two  pieces. 



(Before  proceeding  to  the  study  of  Shells,  there  should  be  a 
recapitulation  of  all  the  children  have  learnt  concerning  the 
animals,  and  a  summary  read  to  them  and  written  down  by 


The  mollusks  have  a  soft,  cold,  slimy,  and  con- 
tractile body  moved  by  muscles.  They  have  no 
articulated  moveable  parts  as  limbs  ;  in  some, 
the  organs  of  motion  are  tentacula  of  different 
forms ;  in  others,  a  fleshy  foot  extending  along 
the  underpart  of  their  bodies ;  this  fleshy  sub- 
stance is  sometimes  free  and  pliable,  and  can  be 
projected  and  drawn  in  at  pleasure.  The  bodies 
of  the  mollusks  are  enveloped  in  a  sac  or  mantle 
of  skin  full  of  pores  and  glands,  which  some- 
times spreads  over  their  shell.  They  are  desti- 
tute of  bones.  They  have  not  red  warm  blood, 
but  a  white  cold  fluid  circulates  through  their 
frames  in  vessels  issuing  from  a  heart.  They 
have  nerves  connected  with  their  different  organs. 
They  are  divided  into  two  classes.  The  first, 
mollusca  cephala,  have  a  distinct  head,  bearing 
lips  or  jaws,  and  are  furnished  with  eyes  and 
tentacula.  The  second,  mollusca  acephala,  have 
a  more  simple  organization  ;  they  have  no  dis- 
tinct head,  and  are  destitute  of  jaws  and  other 
hard  parts  of  a  mouth ;  they  inhabit  shells 
formed  of  two  pieces. 




Teacher.  Well,  did  you  find  the  study  of 
the  mollusca  as  uninteresting  and  unprofitable 
as  you  expected  it  to  be  ? 

Child.  Oh  no,  we  have,  on  the  contrary, 
learnt  much  that  has  interested  and  surprised  us. 

Teacher.  And  what  useful  lesson  may  you 
apply  to  yourselves  from  the  mistake  you  first 
made  ? 

Child.  Not  to  look  upon  any  of  the  works 
of  God  with  indifference  or  contempt,  but  to 
feel  convinced  that  if  they  fail  to  excite  our 
admiration,  it  is  on  account  of  our  ignorance. 

Teacher.  The  more  you  study  Natural  His- 
tory, the  more  you  will  be  inclined  to  acknow- 
ledge this  truth.  Now  I  wish  you  to  examine 
the  coverings  of  the  mollusks, — are  there  any 
parts  of  other  animals  that  can  be  compared  to 
shells  ? 

Child.  The  hard  coverings  of  beetles  are 
something  like  them. 

Teacher.  What  strikes  you  as  being  the 
principal  difference  between  shells  and  the  case 
in  which  some  insects  are  enclosed  ? 

Child.  Shells  are  like  houses  ;  but  the  cover- 
ings of  insects  fit  the  different  members  of  their 

SHELLS.  25 

bodies  like  a  skin,  and  seem  to  be  a  part  of  the 
animal  itself. 

Teacher.  The  coverings  of  insects  are  united 
to  their  different  members ;  but  shells  are  at- 
tached to  the  mollusks  only  in  one  or  two  places 
by  muscles.  You  must  have  had  the  opportunity 
of  observing  how  they  adhere  in  one  spot  to  their 

Child.  Yes,  you  are  obliged  to  cut  the 
oyster  away  from  the  shell. 

Teacher.  Besides  the  difference  which  you 
have  observed  in  the  covering  of  insects  and 
mollusks,  their  composition  is  not  the  same. 
You  remember  learning  in  your  lessons  on  lime,* 
the  animal  substances  of  which  it  forms  a  prin- 
cipal part. 

Child.  Yes,  our  bones  consist  principally  of 
carbonate  of  lime,  and  I  think  you  said  that 
shells  were  also  a  calcareous  substance. 

Teacher.  Shells  are  composed  of  carbonate 
of  lime,  with  the  addition  of  a  small  portion 
of  an  animal  substance  called  gelatine  :  the 
covering  of  insects  is  a  phosphate  of  lime.  The 
substance  of  shells  is  testaceous,  having  the 
hardness  of  baked  earthenware,  in  latin,  test  a  ; 
and  hence  the  mollusca  enclosed  in  them  are 
called  testaceous  mollusca  :  the  covering  of  in- 
sects is  crustaceous,  having  the  hardness  of  crust, 
in  latin,  crust  a. 

Child.     But  whence  is  the  carbonate  of  lime, 

*  See  Lessons  on  Objects,  page  173,  Sixth  Edition. 

26  LESSON  V. 

of  which  shells  are  composed  obtained  ?     Is  it 
found  in  the  sea  ? 

Teacher.  It  exudes  from  the  skin  of  the 
animal,  which  as  I  told  you,  is  furnished  with 
numerous  glands.  In  these  is  secreted  the  cal- 
careous matter. 

Child.  How  very  wonderful  that  they  should 
thus  be  provided  with  materials  to  make  their 
abode  ;  but  how  is  the  shell  formed  from  this 
substance  ? 

Teacher.  The  little  animal  you  formerly 
despised  is  its  own  architect,  and  constructs  a 
dwelling  exactly  suited  to  its  wants.  One  of  our 
divines  who  has  written  a  volume  to  prove  that 
the  works  of  creation  are  alone  a  sufficient  evi- 
dence of  the  existence  of  a  wise  and  beneficent 
God,  says,  speaking  of  a  shell,  "  I  do  not 
know  whether  weight  being  given,  art  can  pro- 
duce so  strong  a  case  as  some  shells."*  What 
do  you  now  think  of  the  workmanship  of  these 
little  creatures? 

Child.  It  is  very  wonderful,  and  how  re- 
markable that  there  should  be  such  a  variety  of 
shapes  in  shells  ! 

Teacher.  The  shape  of  the  shell  is  deter- 
mined by  that  of  the  animal  itself. 

Child.  But  the  mollusk  does  not  always 
continue  the  same  size. 

Teacher.  Very  true.  It  is  quite  minute 
when  it  comes  out  of  the  egg,  and  the  shell  is 

*  Paley's  Natural  Theology. 

SHELLS.  27 

then  proportionably  small  ;  but  as  the  animal 
increases  in  size,  it  adds  to  the  dimensions  of 
its  shells  by  additions  made  at  the  opening,  and 
to  its  thickness  by  a  succession  of  layers  de- 
posited within. 

Child.  Do  the  mollusks  always  construct 
their  shells  of  the  proper  shape  ? 

Teacher.  Yes,  the  carpenter  with  his  rule 
and  compass  is  not  so  exact  and  unerring  as 
these  heaven-taught  builders.  But  is  form  the 
only  point  that  attracts  your  attention  in  these 
shells  ? 

Child.  Oh  no ;  they  have  most  beautiful 
colours  and  markings  ;  these  cannot  belong  to 
the. carbonate  of  lime. 

Teacher.  No,  and  again  I  shall  excite  your 
admiration  of  the  little  animal,  when  I  tell  you 
that  he  not  only  constructs,  but  also  adorns  his 

Child.  But  whence  can  he  procure  such 
beautiful  colours  ? 

Teacher.  He  is  furnished  in  himself  with  all 
that  is  necessary  both  for  the  constructing  and 
beautifying  his  shell ;  his  skin  you  remember  is 
full  of  pores ;  these  contain  colouring  fluids, 
which,  penetrating  the  calcareous  substance 
before  it  is  hardened,  form  its  diversified  tints. 

Child.  It  seems  very  wonderful  that  so 
many  shells  should  have  the  same  pattern. 

Teacher.  It  is  indeed  most  wonderful.  I  can 
tell  you  however  how  it  is  supposed  to  be  effected . 
The  pores  containing  the  colouring  matter  are 

28  LESSON  V. 

arranged  in  the  skin  of  the  mollusks  with  the 
same  undeviating  regularity  as  the  spots  upon 
the  leopard,  or  the  stripes  upon  the  tiger,  and 
when  the  liquid  exudes^  it  stains  the  shell,  and 
the  uniformity  of  the  pattern  is  the  consequence 
of  the  order  in  which  the  pores  are  placed  in  the 
mantle.  Now  look  at  all  these  shells,  and  con- 
sider them  only  in  reference  to  their  colours  and 

Child.  The  colours  in  some  are  very  beauti- 
ful, and  there  is  great  variety  of  patterns. 

Teacher.  This  is  very  true  ;  but  are  they 
all  different  ? 

Child.  No,  there  are  some  that  have  quite 
the  same  pattern. 

Teacher.  Then  you  may  observe  two  points 
especially  with  regard  to  the  markings ;  what 
are  they  ? 

Child.  That  there  is  a  very  great  variety, 
and  yet  some  are  alike. 

Teacher.  Do  you  suppose  that  their  being 
alike  is  accidental  ? 

Child.  Oh  no,  it  could  not  have  arisen  from 

Teacher.  Very  true,  nor  can  we  fail  to  ob- 
serve, that  however  great  the  variety  may  be  in 
individual  specimens,  all  the  works  of  creation 
present  a  beautiful  principle  of  order  and  uni- 
formity. Prove  if  you  quite  understand  what 
I  mean,  by  applying  it  to  these  shells. 

Child.     There  is  a  very  great  variety  of  pat- 

SHELLS.  29 

terns  and  shapes,  and  yet  they  are  all  alike  in 
many  respects. 

Teacher.  They  have  undoubtedly  all  a 
general  resemblance,  which  enables  you  at  once 
to  determine  that  they  are  shells  ;  but  more  than 
this,  do  you  not  observe  that  some  are  more 
alike  than  others  ? 

Child.  There  are  some  that  are  very  much 
alike  in  shape. 

Teacher.  Yes,  and  yet  differ  in  other  res- 
pects ;  but  is  this  all  that  you  observe  ? 

Child.  No,  there  are  some  that  appear  ex- 
actly alike. 

Teacher.  Thus  when  you  look  at  a  collection 
of  shells  for  the  first  time,  you  are  struck  by 
their  general  similarity,  and  you  at  once  call 
them  all  shells.  After  a  little  inspection,  it 
will  be  evident  that  amongst  them,  some  have  a 
few  points  qf  resemblance,  and  that  others  are 
quite  alike  in  all  respects.  Thus  you  begin  to 
perceive  that  the  variety  which  at  first  almost 
bewildered  you,  is  limited  by  a  principle,  and 
whilst  your  eye  is  gratified  by  the  diversity, 
your  judgment  is  satisfied  by  the  order  you  find 
preserved.  Tell  me  a  similar  circumstance  in 
another  class  of  natural  objects. 

Child.  Flowers  afford  one.  All  roses  are 
alike  in  general  appearance,  but  the  Moss  Rose 
is  easily  distinguished  from  the  China  Rose. 

Teacher.  The  variety  exhibited  in  the  works 
of  nature  cannot  fail*  to  delight  us,  and  the  re- 
semblances observable  in  them  enable  us  to 

30  LESSON  V. 

classify  and  arrange  them.  There  is  still  one 
point  with  respect  to  shells  which  we  have  not 
considered ;  I  mean  the  situations  which  they 
occupy.  Where  are  shells  found? 

Child.  Most  of  them  in  the  sea,  but  some  on 
land,  and  others  in  ponds  and  rivers. 

Teacher.  Those  which  live  on  land,  are 
called  terrestrial,  from  the  Latin,  terra,  earth. 
These  mollusks  feed  on  vegetables,  and  have  al- 
ways four  tentacula,  and  their  eyes  are  placed 
at  the  tips  of  these  organs.  The  shells  which 
are  found  in  fresh  water,  are  called  fluviatile, 
from  the  Latin  fluviws,  a  river;  they  are  gene- 
rally of  a  corneous  colour,  and  are  semitrans- 
parent  ;  their  mollusks  have  only  two  tentacu- 
la, which  are  flat,  having  eyes  at  the  base. 
The  shells  inhabiting  the  sea  are  termed  marine, 
from  the  Latin,  mar  e,  the  sea ;  they  are  much 
the  most  numerous,  the  most  beautiful,  and  the 
most  highly  prized.  I  will  now  recapitulate  to 
you  the  substance  of  the  lesson  of  to-day,  and 
you  must  write  it  on  your  slates.* 

Shells  resemble  the  hard  coverings  of  insects; 
the  principal  difference  between  them  is,  that 
the  former  are  only  attached  to  the  animal  in 
one  or  two  places,  while  the  hard  case  of  insects 

*  It  would  be  desirable  before  the  recapitulation,  that  the 
teacher  should  question  the  pupils  upon  the  points  that  have 
been  discussed,  as  in  a  preceding  lesson. 

SHELLS.  31 

fits  the  members  of  their  bodies,  and  has  more 
of  the  nature  of  a  skin.  The  substance  also 
differs ;  that  of  shells  is  a  carbonate  of  lime,  with 
a  small  portion  of  an  animal  substance  called 
gelatine,  and  is  termed  testaceous ;  the  case  of 
insects  is  a  phosphate  of  lime,  and  is  called 
crustaceans.  The  carbonate  of  lime,  of  which 
the  shells  are  formed,  is  secreted  in  the  glands 
of  the  mantle,  and  oozing  out,  takes  the  form  of 
the  animal,  and  gradually  hardens.  When  the 
mollusk  is  small,  the  shell  is  proportionably  so ; 
but  as  the  animal  increases,  it  adds  to  the  dimen- 
sions of  its  abode  by  additions  at  the  opening, 
and  to  its  thickness  by  layers  from  within.  The 
colour  and  markings  with  which  the  shells  are 
diversified,  are  produced  in  the  pores  of  the 
mantle,  and  are  there  arranged  in  the  same  pat-  , 
tern  as  that  which  appears  on  the  shell.  Shells 
are  either  terrestrial,  tiuviatiie,  or  marine. 


Teacher.  Let  us  now  consider  in  what  situa- 
tions shells  are  placed.  They  are,  as  you  know, 
exposed  to  the  dashing  of  the  waves,  borne  by 
the  violence  of  storms  against  rocks ;  and  car- 
ried down  rapid  rivers.  You  can  readily  imagine 

32  LESSON  VI. 

the  consequences  of  their  being  situated  amidst 
such  perils. 

Child.  Yes.  The  shells  must  frequently  be 
broken,  and  the  poor  animals  perish. 

Teacher.  Your  first  conclusion  is  true.  The 
shells  are  often  broken  or  injured;  but  God 
always  makes  a  suitable  provision  for  the  cir- 
cumstances under  which  he  places  his  creatures. 
Recollect  that  the  same  Almighty  Being  who 
rules  the  tempests,  directs  also  the  movements 
of  the  minutest  animals,  he  knows  every  effect 
of  the  former  upon  the  latter,  for  he  sees  all  the 
workings  of  his  mighty  plan.  I  am  sure  that 
you  must  know  from  scripture  that  such  is 
the  case. 

Child.  Yes ;  without  Him  not  a  sparrow 
falleth  to  the  ground. 

Teacher.  This  providential  care  is  very 
evident  in  the  history  of  mollusks.  We  find 
that  the  construction  of  the  shell  varies  accor- 
ding to  the  situation  in  which  it  is  placed. 
Some  shells  found  in  the  rapid  rivers  of 
America,*  are  fitted  by  their  great  hardness  and 
thickness  to  contend  with  the  most  boisterous 
elements;!  others  on  the  contrary,  by  their  very 
lightness,  seem  constructed  to  float  on  the  sur- 
face of  the  sea,  and  offering  no  resistance,  are 
carried  along  gently  by  its  waves.  Some  of 
the  mollusks,t  by  adding  to  the  weight  of  their 
little  bark,  are  enabled  to  descend  and  seek  a 

*  The  Unio.  t  Helix  lanthina.  %  Nautilus. 

SHELLS.  33 

shelter  in  the  deep  of  the  ocean ;  some  *  you 
have  learnt,  anchor  themselves  to  rocks  and 
thus  bid  defiance  to  dangers.  But  in  spite  of 
all  these,  and  many  more  equally  beautiful  con- 
trivances, a  breach  is  often  effected  in  the  habi- 
tation of  the  mollusca. 

Child.  And  then  the  poor  animals  must 
perish  ? 

Teacher.  This  is  by  no  means  inevitably  the 
case,  for  they  are  gifted  with  the  power  of  re- 
pairing their  shells. 

Child.     How  can  they  manage  this  ? 

Teacher.  By  a  discharge  of  the  same  cal- 
careous matter,  of  which  they  at  first  constructed 
their  shells.  You  might  by  your  own  expe- 
rience prove  this  to  be  true ;  if  you  procure 
in  the  spring  some  common  snails,  break  off 
a  part  of  their  shells,  then  giving  them  a  supply 
of  food,  place  them  under  a  glass  that  you  may 
watch  their  operations.  You  would  observe 
first  a  frothy  matter  exuding  from  that  part  of 
the  animal  which  you  had  uncovered,  and  form- 
ing a  film ;  in  a  short  time  a  second  discharge 
would  raise  the  first  to  the  level  of  the  external 
surface  of  the  shell,  and  by  degrees  fresh  acces- 
sions would  give  the  new  part  the  thickness  and 
substance  of  the  old  shell. 

Child.  It  would  be  very  amusing  to  watch 
this  experiment. 

Teacher.     But  do  you  not  admire  the  instinct 

*  Pinna. 

34  LESSON  VI. 

that  so  wonderfully  directs  these  little  animals 
in  their  self- preservation  ? 

Child.  It  is  very  surprising  certainly,  that 
such  a  worm  should  have  the  power  of  remedying 
so  great  disasters.  But  could  not  God  have 
enabled  them  to  form  their  shell  at  first  too 
strong  to  be  liable  to  imjuries,  or  else  have 
placed  them  out  of  the  reach  of  danger  ? 

Teacher.  Doubtless  God  could  have  done 
either.  But  all  creation,  as  it  is  now  constituted, 
reads  us  the  lesson  which  we  ought  never  to 
forget,  that  the  work  which  was  pronounced 
*'  good,"  when  it  first  came  from  the  Almighty's 
hand,  has  been  marred,  Every  where  we  trace 
the  consequences  of  the  fall — all  nature  in  its 
tendency  to  decay,  shews  the  sentence  of  death 
passed  upon  it,  yet  it  bears  even  in  its  fallen 
state,  the  impress  of  divine  love  and  mercy. 
Now  examine  again  the  shells  before  you,  and 
try  and  discover  where  any  of  them  have  been 

Child.     Several  appear  patched. 

Teacher.  These  patches  mark  where  some 
hole  has  been  covered  over. 

Child.  But  here  are  some  shells  which  have 
regular  seams, 

Teacher.  These  seams  indicate  where  the 
animal,  in  consequence  of  its  own  growth  made 
an  addition  to  its  residence.  Observe  this  shell. 
(Bucinum  flammium)  Can  you  not  trace  the 
gradual  extension  of  the  shell  from  a  very  small 

SHELLS.  35 

Child.  Yes,  it  is  marked  by  a  rib  like  that 
at  the  opening. 

Teacher.  You  will  find  a  great  many  shells 
which  shew  that  they  have  been  enlarged  in  the 
same  manner.  The  fresh  layers  are  parallel  to 
the  margin  of  this  opening  called  the  mouth, 
and  the  meeting  of  the  edges  of  the  new  and 
old  matter  is  often  marked  by  a  ridge  more  or 
less  elevated, 

The  shell  of  the  adult  animal  is  often  armed 
with  inequalities  on  the  surfaces,  as  spines  or 
tubercles,  which  do  not  appear  in  the  young 
shell.  I  will  now  give  you  a  summary  of  the 
lesson  of  to-day, 


The  mo  11  use  a  are  often  placed  in  situations 
of  great  danger.  They  are  exposed  to  the 
dashing  of  the  waves,  often  borne  by  th«  vio- 
lence of  storms  and  cast  against  rocks  or  stones. 
Some  placed  in  rapid  rivers  are  occasionally 
hurried  along  by  the  impetuosity  of  the  stream, 
God,  however,  always  makes  a  suitable  provi- 
sion for  the  circumstances  under  which  he  places 
his  creatures,  and  when  he  apportions  to  them 
spots  of  danger,  arms  them  with  the  means  of 
protection  and  defence.  Thus  we  find  that  the 
shell  and  the  habits  of  the  mollusca  are  adapted 
to  the  situations  which  they  occupy.  Some  that 
belong  to  the  rapid  rivers  of  America  have  an 
exceedingly  hard  and  substantial  shell,  fitted  to 
contend  with  the  most  boisterous  elements  ; 

36  LESSON  VI. 

others,  on  the  contrary,  by  their  very  lightness 
are  enabled  to  float  on  the  surface  of  the  water, 
and  offering  no  resistance,  are  gently  carried 
along  by  its  waves  ;  some  anchor  themselves 
securely  by  a  byssus  to  rocks,  and  thus  bid  defi- 
ance to  danger ;  others,  by  adding  to  the  weight 
of  their  bark  can  descend  and  seek  a  shelter  in 
the  bed  of  the  ocean.  There  are  many  other 
beautiful  contrivances  for  their  preservation. 
But  in  spite  of  these,  a  breach  is  sometimes 
made  in  their  shell ;  but  this  they  have  the 
power  of  repairing,  by  exuding  a  calcareous 
matter,  similar  to  that  with  which  they  at  first 
constructed  the  shell. 


Teacher.  To-day  you  shall  tell  me  all  that 
you  remember  respecting  shells,  and  I  will  put 
it  together  in  a  more  regular  manner. 


Shells  are  the  coverings  or  habitations  of  a 
species  of  mollusca.  They  are  formed  by  the 
animal  itself  of  carbonate  of  lime  and  gelatine  : 
these  substances  are  secreted  in  glands  in  its  body. 
The  colouring  matter  exudes  from  the  pores 
of  the  mantle,  penetrates  the  shell  before  it  is 
hardened,  and  the  colours  being  arranged  in 

SHELLS.  37 

order  in  the  mantle,  produce  the  peculiar  mark- 
ings which  belong  to  the  different  species. 
When  any  accident  happens  to  the  shell,  the 
animal  is  enabled  to  repair  it.  The  size  of  the 
shell  is  in  proportion  to  that  of  its  inhabitant ; 
small  at  first,  but  is  increased  from  time  to  time, 
till  the  animal  has  attained  its  full  size. 

Teacher.  Before  we  enter  more  fully  upon 
the  study  of  shells,  and  their  classification,  I 
wish  to  direct  your  attention  to  two  circum- 
stances very  conspicuous  in  the  works  of  the 
Creator.  The  first  is,  the  economy  displayed 
by  God  ;  *  you  seem  surprised. 

Child.  Tfes,  it  is  so  very  extraordinary  to 
talk  of  God  beipg  economical,  when  every  thing 
is  at  his  disposal,  and  he  can  create  at  his 

Teacher.  Do  you  not  recollect  our  Saviour 
giving  an  example  of  economy  at  the  very  time 
that  he  was  manifesting  his  omnipotence  ? 

Child.  Yes,  after  he  had  fed  the  multitude 
with  the  two  loaves  and  five  small  fishes,  he 
commanded  that  the  fragments  should  be  gathered 
up,  that  nothing  be  lost. 

Teacher.  The  same  principle  is  displayed  in 
the  works  of  creation.  Nothing  is  superfluous 
or  without  its  use.  The  second  principle  to 
which  I  wish  you  to  give  your  attention  is,  The 
compensatory  providence  of  God. 

*  Paley's  Natural  Theology, 


Child.     What  does  that  mean  ? 

Teacher.  To  compensate  is  to  make  amends 
for  any  defect,  or  to  give  something  of  equal 
value,  for  any  thing  taken  away.  In  nature  we 
often  find  objects  in  which  there  appear  numerous 
deficiencies,  but  on  further  examination  we  dis- 
cover that  these  are  compensated  or  made  up 
by  some  admirable  contrivance.  To  make  this 
clear  to  you,  we  will  reflect  upon  a  well-known 
instance.  Consider  the  spider.  What  is  its  food  ? 

Child.     Flies  and  other  insects. 

Teacher.  And  what  mode  of  pursuit  should 
you  think  best  adapted  to  catching  such 
creatures  ? 

Child.     Flying,  but  the  spider  has  no  wings. 

Teacher.  Here  then  appears  a  sad  deficiency  : 
winged  insects  are  the  natural  food  of  the  spider, 
and  he  has  not  the  means  of  pursuing  them. 
Yet  do  you  not  perceive  how  God  has  compen- 
sated this  deficiency  ? 

Child.  You  mean  by  teaching  him  to  con- 
struct a  web  to  entrap  the  flies. 

Teacher.  This  instance  will  give  you  a  good 
idea  of  what  is  meant  by  the  compensatory  pro- 
vidence of  God.  It  is  much  displayed  in  the 
singular  fitness  of  shells  for  their  respective 
localities.  Thus  those  which  move  easily  from 
place  to  place,  and  consequently  are  able  to 
elude  their  pursuers,  are  often  adorned  with 
vivid  colours,  whilst  those  which  are  incapable 
of  locomotion,  escape  the  notice  of  their  ene- 
mies by  resembling  in  colour  the  stones  and 

SHELLS.  39 

weeds  which  surround  them.  Now  tell  me  the 
two  principles  which  are  to  be  traced  through- 
out the  works  of  the  Creator. 

Child.  The  economy  of  God  and  his  com- 
pensatory providence. 

Teacher.  Bear  these  principles  in  mind,  and 
you  will  see  many  illustrations  of  them  in  the 
habits  of  the  mollusca.  The  following  lines  of 
Pope  will  help  to  fix  them  in  your  memories : 

Nature  to  these,  without  profusion^  kind, 
To  proper  organs,  proper  powers  assigned  ; 
'  Each  seeming  want'  compensated  of  course, 
Here  with  degrees  of  swiftness,  there  of  force. 


••  Teacher.  What  do  you  think  will  be  our 
next  step  in  the  study  of  shells  ? 

Child.  To  learn  the  names  of  shells,  and  how 
to  class  them. 

Teacher.  What  do  you  suppose  first  led 
people  to  adopt  classification  ? 

Child.     The  wish  to  arrange  their  shells. 

Teacher.  This  would  be  one  inducement, 
but  there  are  many  more  important  advantages 
connected  with  classification.  Suppose  that  you 
had  found  a  variety  of  shells  on  the  seashore, 
and  wished  to  inform  a  friend  of  the  specimens 


you  had  picked  up,  without  entering  into  a  long 
description  of  each,  what  would  you  do  ? 

Child.     I  would  tell  him  their  names. 

Teacher.  But  if  he  had  never  seen  the  shells 
before,  what  idea  would  the  name  convey  to 
him  ?  If  I  told  you  that  I  had  a  murex  in  my 
hand,  what  notion  would  you  form  of  this  shell  ? 

Child.  None  at  all,  unless  you  shewed  it  to 

Teacher.  But  if  you  had  seen  the  shell, 
observed  its  peculiar  form  and  appearance,  and 
been  told  that  it  was  called  a  murex,  what  would 
then  be  the  effect  of  my  telling  you  that  I  had 
another  murex  in  my  hand  ? 

Child.  I  should  know  exactly  what  kind  of 
shell  you  meant. 

Teacher.  This  will  give  you  some  idea  of 
the  advantages  of  scientific  classification.  In  the 
various  branches  of  natural  history,  those  ob- 
jects which  resemble  each  other  in  essential 
characters  are  formed  into  a  class  or  genus,  a  des- 
cription of  their  points  of  resemblance  is  drawn 
up,  and  a  name  affixed  to  the  class.  When 
we  have  become  acquainted  with  these  charac- 
teristics, the  name  will  recall  to  our  minds  the 
idea  of  the  set  of  things  signified  by  it. 

Child.     A  name  then  becomes  very  useful. 

Teacher.     How  does  it  become  so  useful  ! 

Child.  By  recalling  to  the  mind  the  things 
which  it  signifies. 

Teacher.  What  is  the  class  of  objects  which 
you  are  about  to  study  ? 

SHELLS.  41 

Child.     Shells. 

Teacher.  In  learning  the  names  of  shells  you 
will  learn  also  what  the  names  imply.  The 
science  which  treats  of  shells,  is  called  Concho- 
logy,  from  the  Greek  word  KOVM  (conch£)  a 
shell,  and  Xoyo<;  (logos)  a  discourse.  From  whence 
does  the  shell  derive  its  shape  and  colour  ? 

Child.     From  the  animal  that  inhabits  it. 

Teacher.  What  then  do  you  think  we  ought 
to  study  besides  the  shell  ? 

Child.    The  mollusca. 

Teacher.  Yes.  But  as  we  should  not  be 
able  to  procure  many  of  these  animals,  we  can- 
not pursue  that  branch  of  the  science ;  and  we 
will  therefore  follow  the  classification  of  Linnaeus, 
which  is  founded  on  the  shells.  He  first  divides 
shells  into  three  great  classes.  Here  are  a  large 
number  which  I  will  arrange  in  three  divisions, 
and  you  must  examine  each,  and  observe  in 
what  respect  the  shells  I  have  classed  together 
resemble  each  other. 

Child.  The  shells  in  one  set  are  formed  of 
one  piece,  in  the  other  of  two  pieces,  and  these 
seem  to  have  several  pieces. 

Teacher.  These  distinct  pieces  are  called 
valves.  Where  have  you  ever  heard  of  a  valve  ? 

Child.  A  pump  has  a  ^  valve, — and  steam 
engines  have  valves. 

Teacher.  Can  you  tell  me  what  is  the  use  of 
the  valve  of  a  pump  ? 

Child.  To  prevent  the  water  from  returning 
into  the  pipe  through  which  it  has  passed. 


Teacher.  The  animals  of  these  shells  with 
two  valves  use  these  pieces  for  a  very  similar 
purpose, — to  exclude  the  water.  Now  that  you 
have  found  out  the  distinguishing  character  of 
these  classes,  I  will  give  you  their  names.  Those 
shells  which  are  composed  of  only  one  valve  are 
called  univalves,  from  the  Latin,  un  us  one,  and 
valve.  Shells  composed  of  two  valves  are 
called  bivalves  from  bis  the  Latin  for  twice,  and 
valve.  Shells  composed  of  more  than  two 
valves  are  called  multivalves,  from  mult  us,  the 
Latin  for  many,  and  valve. 


Questions  will  be  given  at  each  division  of  the  subject, 
which  the  children  should  be  able  to  answer  well  without 
assistance,  before  they  proceed  to  a  new  part. 

1.  Describe  the  animals  called  mollusks. 

2.  Which   of    the    different  senses   do  they 
possess  ? 

3.  How  do  they  move  on  land  ? 

4.  By  what  means  do  they  move  in  the  sea  ? 

5.  Describe  the  different  methods  by  which 
they  render  themselves  stationary. 

6.  Describe  the  organs  by  which  they  feed 

7.  Name  the  two  classes  into  which  the  mol- 
lusks are  divided. 

SHELLS.  43 

8.  Describe  how  the  animals   of  these   two 
classes  differ  from  each  other. 

9.  Of  what  substances  are  the  shells  formed  ? 

10.  How  are  they  coloured  ?  and  what  is  sup- 
posed to  occasion  the  regularity  in  the  markings  ? 

11.  How  is  the  form  of  the  shell  regulated  ? 

12.  What  is  there  remarkable  in  the  forma- 
tion of  shells  ? 

13.  Give  some  examples  of  shells  peculiarly 
fitted  for  the  different  situations  they  occupy  ? 

14.  Mention  some  instances  of  the  compensa- 
tory providence  of  God  manifested  in  the  history 
of  the  mollusks  ? 

15.  Into  how  many  classes  are  shells  divided  ? 

16.  How  are  the  shells  of  each  class  distin- 
guished ? 

17.  Give  the  derivation  of  the  names  of  the 



Teacher.     To  what  class  do  all  these  shells 
belong  ?  * 

Child.     To  the  class  of  univalve  shells. 

*  A  variety  of  univalve  shells  should  be  placed  before  the 

44  LESSON  IX. 

Teacher.  I  intend  that  you  shall  study  the 
univalve  shells  first,  because  they  are  the  most 
simple,  and  their  distinguishing  characters  well 
marked ;  but  before  you  can  describe  these 
shells,  you  must  be  well  acquainted  with  their 
parts.  Here  are  some  univalve  shells, — examine 
them  carefully  ;  I  will  give  you  the  names  for 
the  parts,  as  you  discover  them.  First,  tell  me 
which  appear  to  be  the  principal  parts. 

Child.  These  shells  have  two  principal  parts, 
this  which  swells  out,  and  this  which  is  tapering* 

Teacher.  The  swelling  part  is  called  the 
body,*  and  this  which  is  tapering,  the  spire. 
Observe  how  the  spire  is  produced. 

Child.  It  seems  formed  by  the  rolling  round 
of  a  part  of  the  shell. f 

Teacher.  These  parts  that  roll  round  are 
called  whorls,  from  an  old  Saxon  word  signify- 
ing a  round.  What  do  you  remark  in  these 
whorls  ? 

Child.     That  they  gradually  increase  in  size. 

Teacher.  The  largest  forming  the-  body  of 
the  shell  is  called  the  body  whorl,  the  smallest 
is  called  the  first  whorl.  As  the  whorls  succes- 
sively roll  one  round  another,  what  difference  is 
there  in  the  circles  they  describe  ? 

Child.     They  gradually  increase  in  diameter. 

Teacher.  It  is  from  this  circumstance  that 
the  set  of  whorls  is  called  the  spire,  a  word 
derived  from  the  Greek  root  wceif,  (speir,)  which 

*  See  plate  I. 
t  See  Helix  Stagnalis.  Plate  V.  Fig.  3, 

SHELLS.  45 

signifies  convolutions  gradually  increasing  in 
diameter,  just  as  would  be  the  case  in  a  rope 
coiled  up.  In  the  coiled  rope  you  have  the  cir- 
cles rolled  one  within  the  other,  and  lying  flat, 
or  being  in  the  same  plane.  But  if  the  centre 
whorl  is  gradually  raised  above  the  rest,  what 
form  do  you  obtain  ? 

Child.     A  conical  form. 

Teacher.  Do  you  now  perceive  how  the  term 
spire,  originally  derived  from  a  word  that  sig- 
nifies a  set  of  whorls  gradually  increasing  in 
diameter,  can  be  applied  to  a  conical  form  ? 

Child.  Yes;  because  when  the  whorls  rise 
one  above  another,  they  produce  the  conical  form. 

Teacher.  You  will  find  the  whorls  in  shells 
arranged  in  both  the  ways  described.  When 
the  whorls  are  all  upon  the  same  plane,  or  nearly 
so,*  the  spire  is  said  to  be  refuse,  a  word  derived 
from  the  Latin,  re,  back,  and  tus  us,  beaten. 
Tell  me  why  this  term  is  chosen,  and  pick  out 
some  shells  with  retuse  spires. 

Child.  I  should  think  the  spire  is  called 
retuse,  because  the  whorls  appear  beaten  back 
into  the  body. 

Teacher.  Exactly  so;  now  look  at  some 
specimens  that  form  quite  a  contrast  to  these 
retuse  spires. 

Child.  Here  are  some  in  which  the  whorls 
gradually  taper  to  a  very  fine  point ;  what  kind 
of  spire  is  this  ? 

Teacher.  This  very  pointed  spire  is  said  to 
*  See  Conus  Marmoreus.  Plate  II.  Fig.  1. 

46  LESSON  IX. 

be  subulate,*  from  the  Latin  subul  a,  a  pointed 
tool.  The  term  spire  is  now  applied  to  any 
form  resembling  that  produced  by  whorls,  which 
rising  one  out  of  the  other,  and  decreasing  in 
diameter,  though  it  be  not  occasioned  by  whorls. 
You  can,  perhaps,  recollect  an  instance  in 
architecture,  in  which  the  name  is  so  applied. 

Child.     The  spire  of  a  church. 

Teacher.  When  the  spire  of  a  shell  is 
formed  by  whorls,  which  is  generally  the  case, 
it  is  said  to  be  spirally  convoluted,  the  latter 
term  is  derived  from  the  Latin  words,  con  to- 
gether, and  volut  us  rolled.  Now  examine  the 
spire  still  more  attentively,  and  you  will  find 
some  other  parts. 

Child.  There  is  a  line  formed  where  the 
whorls  meet ;  has  this  line  any  particular  name  ? 

Teacher.  Yes,  it  is  called  the  suture,  from 
the  Latin  sutura,  a  seam  or  joining;  do  you 
perceive  any  difference  in  the  sutures  ? 

Child.  Yes,  in  some  shells  it  is  quite  a  ridge, 
and  in  others  it  is  more  like  a  channel. 

Teacher.  When  it  is  raised  like  a  ridge  or 
keel,  it  is  called  carinate,  from  the  Latin  carin  a, 
a  keel ;  when  it  is  a  sunken  line,  it  is  said  to  be 
channelled.  Now  look  at  your  shells  again. 

Child.  Are  any  parts  of  the  shell  considered 
to  be  the  top  and  bottom. 

Teacher.  Yes,  the  point  of  the  spire  is  the  top. 
You  recollect  what  the  top  and  bottom  of  a  cone 

*  See  Buccinum  Subulatum.    Plate  III.  Fig.  4. 

SHELLS.  47 

are  called,  and  you  may  apply  these  terms  to 

Child.  The  point  of  the  spire  is  then  the  apex, 
and  the  part  immediately  opposite,  the  base. 

Teacher.     You  are  right. 

Child.  I  think  that  when  you  described  to  us 
how  the  shells  were  enlarged,  you  called  the 
opening  the  mouth. 

Teacher.  Yes,  it  is  termed  either  the  mouth 
or  aperture. 

Child.     Shells  have  also  sides. 

Teacher.  Yes,  and  it  is  necessary  that  you 
learn  to  distinguish  the  two  sides.  You  are 
supposed,  when  you  describe  a  shell,  to  place  it 
upon  its  base  with  its  mouth  turned  towards 
you  ;  the  right  side  will  then  be  that  nearest 
to  your  right  hand,  and  the  left  that  nearest 
your  left  hand. 

Child.  What  is  the  part  turned  toward  me 
called  ? 

Teacher.  The  front,  and  what  do  you  sup- 
pose the  reverse  is  ? 

Child.    The  back. 

Teacher.     Look  at  this  section  of  a  shell.* 

Child.  Is  it  cut  down  the  middle  that  we 
may  observe  the  inside  ? 

Teacher.     Yes  ;  and  what  do  you  perceive  ? 

Child.  There  is  a  pillar  round  which  the 
whorls  appear  to  wind. 

Teacher.   This  pillar  is  called  the  Columella, 
from  the  latin  colum  ella,  a  little  column. 
*  See  Section  of  a  shell.    Plate  I. 

48  LESSON  IX. 

Child.  Have  we  now  mentioned  all  the  parts  ? 

Teacher.  No,  you  must  examine  your  shells 
more  attentively. 

Child.     The  edges  of  the  mouth. 

Teacher.  By  what  name  are  the  edges  or 
borders  of  our  mouths  called  ? 

Child.  Lips.  Is  the  same  term  applied  to 
the  edges  of  the  mouth  of  shells  ? 

Teacher.  Yes,  and  you  must  distinguish 
these  two  lips.  What  is  their  position  ? 

Child.     One  is  on  the  outside  of  the  mouth. 

Teacher.  That  is  called  the  outer  lip,  and 
where  is  the  other. 

Child.     Upon  the  body  whorl. 

Teacher.  To  which  part  of  the  shell  is  it 
near  ? 

Child.     It  is  near  to  the  columella. 

Teacher.  It  is  thence  called  the  Columellar 
lip.  In  what  respect  do  these  lips  resemble 

Child.     They  are  the  borders  of  the  mouth. 

Teacher.  Right.  But  how  do  they  differ 
from  our  lips  ? 

Child.     They  are  not  moveable. 

Teacher.  Do  you  suppose  this  is  any  disad- 
vantage to  the  animal  ? 

Child.  I  should  think  it  is,  for  he  cannot 
close  his  mouth,  and  exclude  the  water  or  keep 
out  enemies. 

Teacher.  True,  but  those  species  which 
would  suffer  from  such  an  exposure,  are  pro- 
vided with  a  kind  of  lip  which  fits  into  the  mouth 

SHELLS.  49 

and  closes  the  entrance  to  the  shell,  when  the 
animal  retires  within  it.  This  lid  is  called  the 
operculum,  a  latin  word,  signifying  a  covering. 
The  shells  which  are  furnished  with  this  appen- 
dage, are  said  to  be  operculated.  Did  you  ever 
observe  anything  at  all  like  it  in  the  snails  ? 

Child.  The  entrance  to  the  shell  is  guarded 
by  a  thin  covering  during  the  winter. 

Teacher.  The  animals  belonging  to  land 
shells,  as  for  instance  snails,  protect  themselves 
from  the  inclemency  of  winter,  by  forming  a 
temporary  covering,  which  adheres  to  the  sides 
of  the  shell,  and  is  deciduous, — that  is,  falling 
after  a  certain  period,  from  Latin  decido,  I 
fall.  The  operculum  of  the  marine  shell  is 
of  a  very  different  nature.  It  is  either  a  calca- 
reous or  horny  substance,  is  permanent,  and  not 
attached  to  the  shell,  but  to  the  foot  of  the 
animal,  who  draws  it  over  the  mouth  when  he 
recedes  into  his  abode.  Now  tell  me  the  position 
of  the  mouth. 

Child.     It  is  on  the  right  side  of  the  shell. 

Teacher.  Observe  whether  that  is  invariably 
its  place. 

Child.  No,  here  is  one  shell  it  which  it  is  on 
the  left  side. 

Teacher.  This  is  the  case  in  some  few  species, 
and  the  shell  is  then  said  to  be  sinistral,  a  word 
derived  from  the  Latin  sinistra,  the  left  hand. 
The  others  are  called  dextral  shells,  from  dextra 
the  Latin  for  the  right  hand.  The  sinistral  shells 
are  also  said  to  be  reversed,  because  the  whorls 

50  LESSON  IX. 

proceed  in  a  direction  contrary  to  their  usual 
course.  Now  look  at  this  very  singular  shell. 
(Murex  haustelium.) 

Child.     It  has  a  long  tube. 

Teacher.     From  what  does  it  proceed  ? 

Child.     From  the  mouth. 

Teacher.  Do  you  recollect  any  animals  that 
have  a  similar  projection  proceeding  from  their 
mouths  ? 

Child.  Oh  yes ;  birds,  their  beaks  are  like 
this  part  of  the  shell. 

Teacher.  This  projection  in  shells  is  also 
called  a  beak,  or  rostrum,  the  Latin  for  beak. 

Child.     The  beak  is  hollow. 

Teacher.  It  is  ;  the  interior  is  called  the  canal 
and  the  shells  which  have  these  beaks  are  said  to 
be  canaliculated ;  and  when  the  aperture  has  not 
a  beak  or  canal,  it  is  called  entire. 

Child.     Is  the  beak  of  any  use  ? 

Teacher.  Yes,  the  animals  which  have  this 
beak  have  an  elongated  fleshy  tube,  which  is  in 
some  way  connected  with  their  breathing. 

Child.  Many  of  the  shells  have  projections, 
some  resembling  thorns,  some  ridges,  and 
some  rounded  protuberances. 

Teacher.  The  projections  resembling  thorns 
are  called  spines,  and  the  shells  which  have  them 
are  said  to  be  spinous.  The  rounded  projec- 
tions are  termed  tubercles,  and  the  shells  on 
which  they  appear  are  called  tuberculous.  The 
ribs  which  are  longitudinal  rounded  sutures 
formed  at  the  various  growths  of  the  shell  are 

SHELLS  .  51 

called  varices,  from  the  Latin  varix,  a  swollen 
vein.  But  such  parts  as  occur  only  in  a  few 
species  we  will  notice  when  we  examine  the 
species.  You  must  now  repeat  to  me  the  parts 
of  a  univalve  shell,  and  I  will  write  them  on  the 


The  spire, 
body  whorl, 
first  whorl, 

columellar  lip. 
outer  lip. 
right  side, 
left  side, 

Teacher.     Describe  to  me  each  part  and  its 

Child.     The  spire  is  composed  of  the  upper 

•52  LESSON  IX. 

whorls,  and  is  situated  at  the  upper  part  of  the 

The  whorls  are  the  parts  that  roll  round  and 
form  the  spire. 

The  first  whorl  is  the  smallest  whorl,  and  is 
at  the  top  of  the  spire. 

The  body  whorl  is  the  largest  whorl,  and  is 
at  the  base  of  the  shell. 

The  suture  is  the  seam  formed  by  the  meeting 
of  the  whorls. 

The  apex  is  the  top  of  the  spire. 

The  base  is  the  opposite  extremity  to  the  apex , 
and  is  situated  either  at  the  lowest  part  of  the 
aperture,  or  at  the  end  of  the  beak,  when  the 
shell  is  canaliculated. 

The  aperture  or  mouth  is  the  entrance  to  the 
cavity  of  the  shell. 

The  lips  are  the  edges  of  the  mouth. 

The  columellar  lip  is  the  lip  nearest  the 

The  outer  lip  is  the  outer  edge  of  the  mouth. 

The  columella  is  the  pillar  round  which  the 
whorls  form  their  spiral  volutions. 

The  fron  t  is  that  part  of  the  shell  in  which  the 
mouth  is  situated. 

The  back  is  opposite  to  the  front. 

The  right  side  is  that  part  of  the  shell  which 
would  be  next  to  the  right  hand  of  a  person 
looking  at  it,  the  front  of  the  shell  being  placed 
opposite  to  him. 

The  left  side  is  that  part  of  the  shell  which 
would  be  next  the  left  hand  of  the  person 

SHELLS.  53 

looking  at  it,  the  front  being  opposite  to 

Teacher.  Give  me  the  derivation  and  appli- 
cation of  the  word  spire. 

Mention  the  different  kinds  of  spires,  with  the 
derivation  of  the  terms  which  you  use. 

Whence  is  the  term  suture  derived  ? 

How  do  the  sutures  vary  ? 

What  different  projections  occur  on  the  sur- 
faces of  shells  ? 

From  what  is  the  term  varices  derived  ? 

How  are  the  cavities  of  the  shells  often 
closed  ? 

Tell  me  the  derivation  of  the  word  operculum. 

What  different  kinds  of  opercula  are  there  ? 

What  are  the  shells  called  which  have  a  beak  ? 

What  is  the  mouth  said  to  be  when  it  has  no 
beak  ?  * 

*  These  model  lessons  have  been  drawn  out  with  great 
minuteness  in  order  to  exhibit  two  principles,  very  important 
to  be  applied  in  this  kind  of  instruction.  1st.  That  the  object 
itself  should  be  presented  to  the  children ;  that  their  powers  of 
observation  may  be  stimulated  and  directed  by  appropriate 
questions ;  and  thus  a  considerable  portion  of  their  knowledge 
be  acquired  by  themselves,  instead  of  all  being  simply 
communicated  by  the  Teacher.  2nd.  That  whatever  supple- 
mentary information  is  given  should  be  reproduced  by  the 
class  before  the  conclusion  of  the  lesson. 



Genus.— CONUS.— Plural,  Coni. 


THE  party  should  have  before  them  a  variety 
of  univalve  shells,  amongst  which  there  should 
be  a  large  proportion  of  such  Cones  as  have  the 
characteristics  of  the  genus  well  defined.* 

Teacher.  I  have  brought  a  variety  of  shells 
for  you  to  examine  ;  what  is  the  point  of  re- 
semblance which  unites  them  all  in  one  class  ? 

Child.  They  are  ail  composed  of  one  valve ; 
they  are  all  univalves. 

Teacher.  From  these  univalve  shells  select 
those  which  appear  to  you  to  be  similar  in  their 
general  appearance,  and  in  the  form  of  their 

Child.     We  have  done  so. 

Teacher.  Explain  to  me  what  you  have  done. 

Child.  We  have  selected  those  shells  which 
have  the  same  general  appearance,  and  a  similar 
kind  of  mouth. 

Teacher.  What  was  the  common  point  of 
resemblance  in  all  the  shells  which  I  have  set 
before  you  ? 

*  It  is  very  important  in  teaching  children  to  draw  out  the 
generic  character  of  shells,  to  set  before  them  specimens  in 
which  the  distinguishing  features  are  strongly  and  clearly 
marked ;  their  ideas  will  then  be  distinct,  vivid,  and  perma- 
nent. After  this  they  may  proceed  to  the  examination  of 
shells,  which,  combining  the  qualities  of  different  genera, 
form  the  connecting  links  between  them. 

CONUS.— CONE.  55 

Child.  Their  being  composed  of  only  one 

Teacher.  And  what  are  the  points  of  dis- 
similarity that  lead  you  to  separate  this  smaller 
set  from  the  whole  group  ? 

Child.  The  difference  in  their  general  ap- 
pearance, and  in  their  mouth. 

Teacher.  You  have  now  formed  a  smaller 
class.  Such  a  subdivision  is  called  a  Genus, 
from  the  latin  word  gen  us,  a  kind ;  the  plural 
of  genus  is  genera.  The  characteristic  distinc- 
tion of  each  genus  among  the  univalves  is  foun- 
ded on  the  general  appearance  of  the  shells,  and 
the  form  of  their  mouth.  The  specimens  which 
you  have  chosen  belong  to  the  genus  called 
Conus,  the  plural  of  which  is  Coni.  You  must 
now  examine  the  shells  carefully  and  try  and 
discover  in  what  respect  they  resemble  each 
other  ;  you  will  then  be  able  to  describe  their 
generic  character,  or  mark  those  qualities  pos- 
sessed in  common  by  them  all,  and  which  dis- 
tinguish them  from  all  other  shells.  How  will 
you  set  about  this  ? 

Child.  We  must  compare  them  together, 
and  put  down  those  qualities  which  they  all 

Teacher.  First  consider  their  general  ap- 

Child.  Their  shape  is  very  similar ;  it  re- 
sembles a  cone. 

Teacher.  Yes,  and  it  is  conical,  and  from 
hence  they  have  received  their  scientific  name, 
Conus,  and  their  common  English  name,  Cone. 

56  LESSON  X. 

Child.  The  name  expresses  very  well  the 
appearance  of  the  genus. 

Teacher.  It  does  ;  but  which  is  the  broadest 
part  of  a  Cone  ? 

Child.     The  base. 

Teacher.  And  is  the  base  the  broadest  part 
of  these  shells  ? 

Child.     No  ;  quite  the  reverse. 

Teacher.  They  are  therefore  said  to  be  in- 
versely conical. 

Child.     The  cones  are  spiral. 

Teacher.     Observe  how  the  spire  is  formed. 

Child.     By  the  whorls. 

Teacher.   And  how  are  the  whorls  arranged  ? 

Child.     They  are  spirally  convoluted. 

Teacher.  Compare  the  spires  of  the  Cones 
with  those  of  the  other  shells  before  you,  and 
tell  me  what  you  remark. 

Child.  The  whorls  scarcely  rise  one  above 
the  other. 

Teacher.  You  remember  what  a  spire  is 
called  when  the  whorls  have  the  appearance  of 
being  pushed  into  the  body  whorl. 

Child.  Such  a  spire  is  called  retuse.  Here 
is  a  Cone  in  which  the  upper  whorls  appear  so 
pushed  into  the  body  whorl  that  the  spire  forms 
almost  a  flat  surface. 

Teacher.  What  then  is  the  character  of  the 
spire  of  the  Cones. 

Child.     The  spire  of  the  Cones  is  retuse. 

Teacher.  Compare  together  all  the  different 
shells  before  you,  and  you  will  find  that  the 


relative  proportion  of  their  parts  varies  very 
much.  In  some  you  will  perceive  that  the 
mouth  is  particularly  large,  in  others  the  spire. 
What  is  the  relative  proportion  of  the  parts  of 
the  cone  ? 

Child.  The  body  whorl  is  very  large,  com- 
pared with  the  other  whorls. 

Teacher.  This  peculiarity  is  expressed  by 
the  term  turbinate  which  is  derived  from  the 
Latin  word  turbin  is,  of  a  whirlwind. 

Child.  Why  is  this  form  of  a  shell  named 
after  a  whirlwind. 

Teacher.  Because  the  first  sweep  of  a  whirl- 
wind describes  a  circle  much  larger  than  those 
which  succeed  when  its  power  is  in  some  degree 
exhausted.  Do  you  not  now  perceive  how 
the  term  is  applicable  to  the  form  you  were 
describing  ? 

Child.  Yes.  The  body  whorl  is  very  large 
in  proportion  to  the  others,  just  as  the  first 
sweep  of  a  whirlwind  is  large  compared  with 
those  that  succeed  it. 

Teacher.  You  have  now  observed  the  general 
appearance  of  the  Conus ;  what  particular  part 
were  you  to  take  into  consideration  in  order  to 
draw  out  the  generic  character  ? 

Child.     The  mouth. 

Teacher.  And  what  do  you  observe  in  the 
mouth  of  the  Cones  ? 

Child.     It  is  long  and  narrow. 

Teacher.  When  the  mouth  is  very  narrow  in 
proportion  to  its  length,  and  also  of  a  nearly 

58  LESSON  X. 

equal  breadth  throughout,  it  is  called  linear, 
from  its  having  the  character  of  a  line.  In  con- 
sidering the  parts  of  an  object,  what  besides 
their  form  strikes  your  attention  ? 

Child.     Their  position  and  direction. 

Teacher.  You  remember  the  usual  position 
of  the  aperture. 

Child.  It  is  almost  always  dextral  or  on  the 
right  side  of  the  shell. 

Teacher.  And  as  this  is  its  usual  position,  it 
is  not  noticed  in  the  generic  character,  indeed 
the  peculiarity  of  a  sinistral  aperture  never  runs 
through  a  whole  genus  of  shells.  But  what  do 
you  observe  with  regard  to  the  direction  which 
the  mouth  of  the  Cone  takes  ? 

Child.  It  is  in  the  direction  of  a  line  passing 
from  the  apex  to  the  base,  that  is  the  length 
of  the  shell. 

Teacher.  And  what  do  you  call  the  direction 
of  a  line  passing  from  the  top  of  a  body  to  its 

Child.  Longitudinal ;  the  aperture  of  the 
Cone  is  longitudinal. 

Teacher.  You  recollect  learning  in  a  former 
lesson  the  proper  term  for  shells  with  a  beak, 
and  also  for  those  without  one. 

Child.  Yes,  those  with  beaks  are  called 
canaliculated,  and  those  without  entire.  The 
mouth  of  the  Cone  is  entire. 

Teacher.  Yes.  A  little  experiment  will  lead 
you  to  detect  another  characteristic  of  this 
genus.  Observe,  I  fill  this  shell  (a  Turbo)  with 


water  to  the  edge  of  the  lips — has  any  of  the 
liquid  run  over  ? 

Child.  No ;  the  shell  holds  the  water  like 
a  cup. 

Teacher.  When  this  is  the  case,  the  mouth 
is  said  to  be  contracted.  But  observe  what  is 
the  consequence  when  I  attempt  to  fill  a  cone 
with  water  up  to  the  lips. 

Child.  The  water  runs  out  before  it  reaches 
the  lips. 

Teacher.  Examine  where  the  liquid  flows 
out,  and  what  is  the  cause  of  this  difference  in 
the  two  shells. 

Child.  The  water  flows  out  at  the  base  of 
the  cone.  In  the  other  shell  the  lips  are  united ; 
in  the  cone  they  are  separated  by  a  small 

Teacher.  This  channel  is  called  a  sinus,  from 
the  Latin  sin  us,  a  curved  line.  If  the  two 
lips  be  separated  by  a  sinus,  liquid  poured 
in  overflows  before  it  reaches  the  lips ;  the  aper- 
ture iii  this  case  is  called  effuse,  from  the 
Latin  fus  us,  which  signifies  poured  out.  You 
have  no  doubt  heard  the  term  effusion  applied 
to  the  overflowing  of  any  liquid  ;  you  ought  now 
to  know  exactly  what  such  an  expression  means. 
Compare  the  columellar  lip  with  the  correspond- 
ing part  of  the  Cone  in  these  shells  (a  Voluta 
and  a  Cypraea.) 

Child.     It  is  smooth. 

Teacher.  Examine  all  your  Cones,  and  see 
whether  they  are  all  quite  smooth. 

60  LESSON  X. 

Child.  No  :  there  are  stripes  at  the  base  of 
some  of  them. 

Teacher.  These  are  called  strice,  the  Latin 
for  stripes.  Are  they  only  perceptible  to  your 
sight  ? 

Child.     I  can  feel  them  also. 

Teacher.  What  kind  of  striae  must  they  be 
if  you  can  perceive  them  by  your  touch  ? 

Child.     They  must  be  raised. 

Teacher.  Yes ;  they  are  slightly  raised  like 
wrinkles,  on  which  account  they  are  called 
rugose  stria,  from  the  Latin  rug  a,  a  wrinkle. 
What  direction  do  they  take  ? 

Child.     An  oblique  direction. 

Teacher.  The  columellar  lip  is  nevertheless 
called  smooth,  because  it  has  but  trifling  eleva- 
tions. How  would  you  describe  the  columellar 
lip  of  a  Cone  ? 

Child.  The  columellar  lip  of  a  cone  is  smooth. 
except  that  it  is  marked  by  a  few  oblique  rugose 

Teacher.  Remember  that  the  stripes  are  only 
occasional,  not  invariable.  Do  you  think  that 
any  quality  in  these  shells  has  escaped  your 
observation  ? 

Child.  They  are  all  prettily  marked  and 
have  a  beautiful  polish. 

Teacher.  True;  but  the  colours  of  shells 
and  the  peculiarities  on  their  surfaces  are  not 
spoken  of  in  the  generic  character ;  these  form 
the  distinctions  of  the  different  species.  We 
will  now  sum  up  what  has  been  said  respecting 

CON  US— CONE.  61 

the  Cones,  and  thus  draw  out  their  generic  char- 
acter. You  must  first  mention  to  which  of  the 
three  great  classes  they  belong  ;  next  their 
general  appearance  ;  and  lastly,  the  form  and 
peculiarities  in  the  aperture. 

*  Genus— CONUS— Plural,  Coni. 

Generic  Character.  Shell  univalve  ;  whorls 
spirally  convoluted,  spire  retuse ;  form  inversely 
conical,  turbinate  ;  aperture  linear,  longitudinal, 
entire,  effuse  at  the  base  ;  columellar  lip 
smooth,  sometimes  marked  at  the  base  with  a 
few  oblique  rugose  striae. 



Teacher.  The  genus  Conus  is  very  easily 
known  by  its  conical  form  and  smooth  columel- 
lar lip ;  these  may  be  considered  its  two  distin- 
guishing characters.  Much  has  not  been  dis- 
covered of  the  history  or  habits  of  the  mollusks 

The  generic  character  should  be  written  on  the  slate  be- 
fore the  children ;  they  should  learn  it,  and  afterwards  occa- 
sionally repeat  it. 

62  LESSON  XI. 

belonging  to  these  shells.  I  will  relate  to  you 
all  the  facts  that  I  have  been  able  to  collect, 
and  you  must  give  your  undivided  attention  to 
what  I  say,  in  order  that  you  may  afterwards 
write  down  the  account  from  recollection. 

The  animal  inhabiting  the  shells  belonging  to 
the  genus  Conus,  breathes  by  means  of  gills  ;  it 
has  two  tentacula  bearing  eyes,  the  mouth  is  a 
long  proboscis,  and  the  foot  is  furnished  with  an 
operculum,  by  which  it  closes  the  entrance  to 
its  shell.  The  section  of  a  Cone  displays  a 
fact  very  interesting,  from  its  illustrating  the  sin- 
gular habit  of  the  mollusks  ;  it  is,  that  the 
internal  whorls  are  of  a  much  thinner  substance 
than  the  external  coating.  It  is  supposed  that 
when  the  animal  by  an  addition  to  its  shell, 
causes  what  was  its  outer  whorl  to  be  surrounded 
and  concealed  by  a  new  one,  that  it  absorbs  a 
portion  of  the  old  whorl,  and  thus  it  diminishes 
the  weight  of  its  shell,  gives  more  room  within 
for  its  body,  and  preserves  the  solidity  and 
strength  of  its  bulwarks.  In  this  we  see  a  beau- 
tiful instance  of  the  superintending  providence 
of  God,  who  by  the  instinct  he  implants,  directs 
the  habits  of  the  animal  kingdom.  The  shells 
of  this  genus  are  remarkable  for  the  regularity 
of  their  form,  the  brillancy  of  their  colours,  and 
the  beautiful  variety  and  distinctness  of  their 
markings.  They  are  usually  covered  with  a 
thick  epidermis,*  which  preserves  the  fine  polish 

Epidermis,  art  outer  skin,  from  the  Greek  CTTI,  (epi)  upon, 
(derma)  a  skin. 


of  the  surface.  They  are  all  natives  of  the 
ocean,  and  are  taken  in  the  seas  of  hot  climates 
where  they  live  at  a  depth  of  about  ten  or 
twelve  fathoms.*  They  are  never  found  on  our 
coasts.  Their  name  is  derived  from  the  Greek, 
Kuvoq  (conos)  a  cone.  Now  attend  and  answer 
the  questions  I  shall  put  to  you  upon  all  that  I 
have  detailed.  What  kind  of  animal  inhabits 
the  cone  ? 

Child.  It  is  one  that  breathes  by  means  of 
gills ;  has  a  pair  of  tentacula  bearing  eyes  ;  and 
its  mouth  is  a  long  proboscis. 

Teacher.  There  is  one  part  of  the  animal 
which  you  have  not  noticed. 

Child.  It  has  an  operculum  attached  to  its 
foot,  with  which  it  closes  the  aperture  of  its  shell. 

Teacher.  What  is  remarkable  in  the  habits 
of  this  rnollusk  ? 

Child.  It  is  supposed  to  absorb  the  matter 
of  which  the  interior  convolutions  of  its  shell 
are  composed. 

Teacher.  What  then  is  the  appearance  of 
the  shell  when  cut  in  halves  ? 

Child.  The  interior  parts  of  the  whorls  are 
thin,  whilst  the  outer  part  of  the  shell  is  thick 
and  strong. 

Teacher.  What  advantage  is  the  animal  sup- 
posed to  derive  from  the  external  convolution 
being  so  much  thicker  than  those  within  the 
shell  ? 

Child.    The  thinness  of  the  interior  diminishes 
*  A  Fathom  is  six  feet. 


the  weight,  and  gives  room  for  its  body,  whilst 
the  thickness  of  the  exterior  preserves  its  strength. 

Teacher.  What  is  there  remarkable  in  the 
appearance  of  these  shells  ? 

Child.  They  are  remarkable  for  the  regular- 
ity of  their  form,  the  brightness  of  their  colours, 
and  the  variety  and  beauty  of  their  markings. 

Teacher.  What  is  their  appearance  when  first 
taken  out  of  the  ocean  ? 

Child.  They  are  generally  covered  with  an 
epidermis,  which  preserves  their  beautiful  polish. 

Teacher.     To  what  seas  do  they  belong  ? 

Child.     To  the  seas  of  warm  climates. 

Teacher.  And  what  is  their  situation  in  the 
ocean  ? 

Child.  About  ten  or  twelve  fathoms  under 
water.  How  much  is  a  fathom  ? 

Teacher.  A  fathom  is  six  feet;  how  many 
feet  then  are  they  under  water  ? 

Child.     Between  sixty  and  seventy  feet. 

Teacher.  From  what  is  the  name  Conus 
derived  ? 

Child.  The  name  conus  is  derived  from  the 
Greek  KMQ<;  (conus)  a  cone. 

The  Teacher  should  again  read  to  the  children  the  facts 
connected  with  the  natural  history  of  the  genus,  and  require 
them  to  give  an  account  in  writing  of  all  they  have  heard. 
For  fear  of  discouraging  them  in  the  outset,  some  assistance 
may  at  first  be  given  ;  but  it  should  be  gradually  withheld, 
and  the  attention  brought  into  vigorous  activity,  that  the  mind 
may  become  able  to  grasp  the  subject  brought  before  it.  The 
first  object  to  be  attended  to  in  their  composition,  is  fluency, 
and  this  will  be  best  promoted  by  allowing  them  to  use  their 



Teacher.  If  any  one  were  now  to  speak  to 
you  of  a  Conus,  what  idea  would  the  name  call 
up  to  your  mind  ? 

Child.  The  name  Conus  would  recall  the  idea 
of  a  univalve  shell,  whose  form  is  inversely 
conical  and  turbinate  ;  the  spire  retuse  ;  whorls 
spirally  convoluted,  aperture  linear,  longitu- 
dinal, entire,  effuse  at  the  base ;  its  columellar 
lip  smooth,  having  sometimes  a  few  oblique 
rugose  striae  towards  its  base. 

Teacher.  Yes,  all  the  shells  before  us  posses- 
these  qualities,  or  they  would  not  be  Cones : — 
but  are  they  alike  in  all  respects  ? 

Child.  No  ;  they  differ  very  much  in  their 
colours  and  patterns,  and  also  in  their  size. 

Teacher.  On  account  of  this  variety  in  the 
shells  possessing  the  same  generic  marks,  the 
different  genera  have  been  subdivided  into 
species,  the  characters  of  which  are  determined 
by -the  circumstances  of  colour,  markings,  size, 

own  expressions,  and  follow  their  own  arrangement  of  the 
subject.  When  they  have  learnt  to  express  themselves  readily, 
they  should  be  taught  to  seek  for  appropriate  language,  and  to 
correct  the  inaccurate  and  inelegant  expressions  in  their  com- 
positions. They  should  also  be  instructed  to  consider  their 
subject  well,  before  they  begin  to  write  on  it,  that  they  may 
arrange  the  matter  in  the  best  order. 


and  the  inequalities  of  the  surface.  Here  is  a 
shell  called  Conus  marmoreus  :  1  wish  you  to 
examine  it,  and  draw  out  its  specific  character  ; 
it  is  considered  as  the  type  or  representative  of 
the  Conus,  from  its  having  the  characteristics 
of  the  genus  strongly  marked.  Now,  tell  me 
what  you  have  to  do. 

Child.     We  must  try  and  describe  this  shell. 

Teacher.  Yes  ;  but  you  must  recollect  that 
you  have  to  point  out  the  specific  distinctions 
only  ;  you  must  now  omit  the  generic  marks,  as 
you  have  already  determined  them,  and  they  are 
implied  in  the  name  Conus.  First,  what  is  the 
size  of  this  Cone?  * 

Child.    It  is  rather  more  than  two  inches  long. 

Teacher.  Yes,  in  length  it  generally  varies 
from  two  to  three  inches.  What  is  the  colour 
of  the  shell,  and  that  of  its  markings  ? 

Child.  The  ground  is  a  dark  chesnut  brown, 
approaching  to  black,  and  the  markings  are 

Teacher.  What  form  do  the  spots  most 
nearly  resemble  ? 

Child.     They  are  nearly  triangular. 

Teacher.  You  may  call  them  white  subtri- 
angular  spots  ;  sub  means  under,  and  when  pre- 
fixed to  an  adjective  implies  that  the  quality 

*  The  children  should  have  the  length  of  an  inch  given 
to  them,  and  by  degrees  they  will  learn  to  determine  the 
dimensions  of  the  specimens  without  measuring  them.  They 
should  also  be  practised  in  deciding  colours  and  their  various 
shades,  by  referring  at  first  to  some  standard.  Werner's 
Nomenclature  of  colours  is  a  useful  work  for  this  purpose. 


attributed  to  the  object,  exists  in  an  inferior  de- 
gree.    Examine  the  substance  of  the  shell. 

Child.     It  is  heavy  and  thick. 

Teacher.  It  is  a  ponderous  shell  ;  now  look 
at  the  spire,  and  tell  me  what  you  remark  in  it. 

Child.  It  has  little  swellings  placed  regu- 
larly at  the  edges  of  the  whorls. 

Teacher.  These  swellings  are  called  tuber- 
cles, and  a  spire  marked  with  such  inequalities 
is  said  to  be  coronated. 

Child.     I  suppose  that  means  crowned. 

Teacher.  Yes,  the  spire  is  so  called  from  its 
crown-like  appearance ;  do  you  observe  any 
other  peculiarity  in  it  ? 

Child.  The  whorls  are  concave,  and  in  most 
shells  they  are  convex. 

Teacher.  The  whorls  in  this  shell  form  a 
little  spiral  channel,  and  are  thence  said  to  be 
channelled.  We  will  now  write  down  the  specific 
character  ;  but  I  must  inform  you,  that  the 
name  marmoreus  is  derived  from  the  Latin 
marmor,  marble ;  and  is  applied  to  these  shells 
on  account  of  their  mottled  appearance. 

CONUS  Marmoreus* 


Specific  Character.  Shell  ponderous,  smooth, 
dark  chesnut  brown,  with  white  sub  triangular 
spots ;  spire  coronated,  whorls  channelled  ;  size, 
from  two  to  three  inches  in  length. 

*  Plate  II.  fig.  1. 
F  2 


Genus.— CYPR^A.*— JVwraJ,  CyprcecB. 

Generic  Character. f  Shell  univalve,  involuted,]: 
smooth  ;  form,  suboval,  resembling  a  coffee 
berry,  obtuse  at  both  ends ;  aperture  linear, 
longitudinal,  extending  the  length  of  the  shell, 
effuse  at  each  end ;  lips  curved  inwards  and 
toothed ;  the  spire  in  some  species  just  percep- 
tible, in  others  its  position  marked  by  an  um- 


The  Cypraeae,  of  which  there  are  numerous 
species,  display  a  high  natural  polish,  uniformity 

*  Plate  II.  fig.  2,  4,  5. 

*f*  The  proposed  manner  of  imparting  instruction  upon 
Natural  History,  so  as  at  the  same  time  to  develop  the  faculties 
of  children,  having  been  fully  shown  in  the  preceding  pages : 
the  substance  only  of  the  lessons  will  now  be  given  for  the 
use  of  the  Teacher ',  who,  it  is  supposed,  will  analyse  it  and 
arrange  it  in  questions  according  to  the  plan  of  the  fore- 
going lessons.  A  frequent  repetition  of  the  generic  character 
is  recommended,  and  also  that  the  children  be  required  occa- 
sionally to  give  a  list  of  the  parts  of  a  shell,  and  definitions 
of  the  terms  they  use. 

+  Involuted.  Rolled  inwards,  this  term  is  applied  to  a  shell 
when  the  first  whorls  are  rolled  within  the  body  whorl,  from 
the  Latin  involut  us9  rolled  up  in. 

§  Umbilicus.  A  small  hollow :  this  term  was  applied  by 
the  ancients  to  the  centre  of  the  shield. 


of  shape,  delicate  and  distinct  markings,  with 
great  beauty  and  variety  of  colours.  They  are 
readily  distinguished  from  all  other  shells  by 
their  lips  being  rolled  inwards,  and  both  of 
them  toothed.  The  history  of  the  genus  is  very 
interesting  from  the  remarkable  difference  which 
occurs  in  the  appearance  of  the  same  shell  at 
the  various  stages  of  its  growth.  In  its  earliest 
state,  the  shell  is  very  thin,  almost  colourless, 
and  dull ;  the  mouth  rather  wide,  the  outer  lip 
not  rolled  inwards,  but  having  a  sharp  edge,  and 
neither  lip  denticulated.  The  shell  which  the 
animal  first  forms  is  indeed  so  dissimilar  to  the 
perfect  Cypraea  that  it  was  formerly  placed  in 
another  genus.  In  the  second,  or  intermediate 
period  of  growth,  the  shell  begins  to  approach 
the  general  form  that  characterizes  the  genus. 
The  lips  are  curved  inwards,  and  the  teeth  be- 
come apparent;  but  the  shell  is  still  thin,  its 
colour  faint,  and  its  markings  seldom  more  than 
ill-defined  tranverse  bands.  In  its  third  and  per- 
fect state,  the  Cypraea  has  received  an  addi- 
tional coating  of  testaceous  matter,  the  pattern 
appears  with  its  vivid  tints,  and  delicate  mark- 
ings, and  the  spire  if  not  entirely  hidden,  yet 
scarcely  projects  out  of  the  body  whorl. 

The  animal  itself  undergoes  a  considerable 
change  during  its  growth,  its  mantle  at  first  is 
small,  but  it  increases  with  its  age,  and  expands 
at  the  sides  into  two  ample  wings ;  from  these  it 
is  that  the  final  layer  which  completes  the  shell 
is  deposited.  In  the  adult  specimens,  these  ex- 


pansions  of  the  mantle  completely  cover  the 
shell,  when  the  animal  goes  forth  to  seek  its 
food  ;  at  the  place  where  they  unite,  a  longitu- 
dinal line  is  formed,  from  its  position  on  the 
back  of  the  shell,  it  is  called  the  dorsal  *  line  ; 
when  the  wings  are  so  large  that  they  fold  one 
over  the  other,  their  place  of  junction  is  not 
marked.  The  external  polish  of  these  shells  is 
owing  to  their  being  so  frequently  covered  by 
the  mantle.  The  animals  inhabiting  theCypraea, 
have  a  fleshy  foot  with  which  they  crawl,  simi- 
lar to  that  of  the  snail  ;  the  head  is  placed  on  a 
neck,  and  has  two  finely  pointed  tentacula, 
with  two  eyes  situated  at  their  base  ;  the  mouth 
is  a  round  opening  armed  with  teeth,  these  latter 
are  not  only  organs  of  nutrition,  but  defensive 
weapons.  The  mantle  in  front  forms  a  kind  of 
tube,  which  is  lodged  in  the  notch  of  the  shell  ; 
through  this  the  mollusk  receives  the  water  it 
breathes.  In  a  state  of  rest  the  Cypraete  remain 
buried  under  the  sea  at  some  distance  from  the 
shore,  but  it  is  said  that  at  full  of  the  moon 
they  quit  this  retreat  and  traverse  the  rocks. 
They  belong  principally  to  the  seas  of  hot  cli- 
mates ;  a  few  species  are  met  with  in  temperate 
regions,  but  these  possess  not  the  beauty  of 
colouring  displayed  by  their  congeners.  f  It  may 
generally  be  observed  with  regard  to  shells,  that 

*  Dorsal,  belonging  to  the  back,  from  the  Latin 
the  back. 

f  Congener  —  one  of  the  same  genus,  from  Latin  con,  to- 
gether, andgenws.  * 


the  intensity  of  their  colouring  decreases  as  their 
locality  approaches  the  poles.  One  species 
called  the  Cypraea  Moneta*  is  the  current 
money  of  Bengal,  Siam,  and  Africa;  it  is 
picked  up  by  the  negro  women  of  the  Indian 
islands  about  the  full  of  the  moon.  This  genus, 
on  account  of  its  great  beauty,  was  formerly 
dedicated  to  Venus,  the  fabulous  divinity  of  the 
island  of  Cyprus,  from  which  circumstance  its 
name  is  derived. 

CYPRAEA  Arabica* 


Specific  Character.  Shell  subovate  ;  colour 
brownish,  or  blueish  white,  inscribed  with  dark 
brown  markings  resembling  Arabic  characters  ; 
the  sides  are  thickened  and  spotted  with  purple  ; 
the  teeth  are  chesnut  brown ;  the  dorsal  streak 
is  simple. 

The  shell  is  from  two  to  three  inches  long, 
the  breadth  is  nearly  three  quaVters  of  its  length. 

The  young  shells  of  this  species  are  blueish 
grey,  variously  clouded  or  banded  with  brown  ; 
when  the  teeth  are  formed,  the  back  appears  of 
a  brownish  or  dull  blue  colour ;  in  this  stage 
of  its  growth,  it  has  been  known  by  the  name 
of  Cypraea  Amethystea,  or  the  Smoke  Cowry. 
Linnaeus  was  not  aware  of  the  change  in  the 

*  Plate  II.  fig.  4.  f  Plate  II.  fig.  2. 


appearance  of  these  Cowries  at  their  different 
periods  of  growth,  and  from  this  defect  in  his 
knowledge,  he  has  described  the  present  species 
under  three  different  names. 

CYPR^EA  Eur&pea* 


Specific  Character.  Shell  ovate,  about  half 
an  inch  long,  and  a  quarter  broad,  trans- 
versely ribbed,  the  ribs  terminating  within  the 
lips ;  of  a  pale  purple  or  flesh  colour,  with 
three  dark  spots  on  the  ridge  of  the  back. 

This  is  a  British  species,  and  found  abun- 
dantly on  our  shores ;  it  greatly  resembles  the 
West  Indian  species,  but  is  distinguished  from 
it,  in  having  no  dorsal  groove,  and  the  dorsal 
spots,  if  there  are  any,  being  limited  to  three. 
Both  the  shell  and  the  inhabitant  vary  so 
much  in  their  different  stages  of  growth,  that 
much  confusion  has  arisen  in  their  classification. 
The  shell  in  its  juvenile  state  is  extremely  thin, 
brittle,  pellucid,  and  quite  smooth  ;  and  the 
animal  of  a  pale  colour,  displaying  no  reflected 
membrane.  In  its  adult  state  the  shell  is  thick, 
opaque,  ribbed,  and  when  the  animal  is  in 
motion  under  the  water,  it  extends  over  it  the 
lateral  appendages  of  its  mantle,  which  are 
speckled  with  a  variety  of  colours,  presenting  a 
very  beautiful  appearance. 

*  Plate  II.  fig.  5. 


Genus.— BULL  A*— Plural,  Bullcs. 


Generic  Character.-^  Shell  univalve,  convo- 
luted, often  without  any  spire,  smooth  ;  J  shape 
suboval,  inflated  ;  aperture  longitudinal,  gene- 
rally the  length  of  the  shell,  entire  at  the  base ; 
columella  oblique,  smooth. 


This  genus  is  perhaps  less  accurately  defined 
than  any  other  of  the  Linnsean  genera  :  it  contains 
an  assemblage  of  shells  presenting  a  very  varied 
appearance  ;  indeed  it  seems  as  if  it  had  been 
formed  to  be  a  receptacle  for  including  all  the 
species  that  could  not  find  a  place  elsewhere. 
The  most  distinguishing  characteristic  of  the 
Bulla  is  its  gibbous  or  inflated  figure,  to  which 
it  owes  its  name,  signifying  water  bubble.  One 

*  Plate  II.   fig.  6,  8,  9. 

f  It  is  hoped  that  Teachers  who  use  these  lessons  will  re- 
collect that  it  is  most  important  when  the  children  are  drawing 
out  the  generic  character,  to  bring  before  them  a  great  variety 
of  shells,  that  they  may  group  them  according  to  resemblances 
which  they  perceive,  and  under  direction  learn  by  observation, 
their  distinctive  characters. 

J  The  Bullae  are  said  to  be  smooth  because  their  surface  has 
never  any  projections. 


species  (Bulla  Ovum)  bears  a  very  striking  re- 
semblance to  the  Cypraea,  it  differs  chiefly 
from  that  genus  by  the  absence  of  teeth  on 
the  columellar  lip.  Some  of  the  Bullae  are 
remarkable  for  having  both  ends  of  the  mouth 
produced  into  long  beaks ;  these  shells  are  called 
birostrate.*  (Bulla  Volva.)  f 

The  inhabitants  of  many  of  the  Bullae  are 
larger  than  their  shells,  in  consequence  they 
cannot  wholly  recede  into  them ;  indeed  in  many 
the  usual  order  is  reversed,  and  the  shell  is  so 
surrounded  and  enveloped  in  the  body  of  the 
animal,  that  no  part  of  it  is  visible,  and  an  in- 
experienced person  would  little  expect  to  find  a 
regular  testaceous  specimen  buried  in  an  unsightly 

A  very  remarkable  circumstance  in  the  animal 
of  the  Bulla,  is  the  form  and  structure  of  the 
stomach,  which  is  furnished  with  a  gizzard ;  this 
organ  is  composed  of  three  strong  shelly  pieces, 
which  have  a  roughness  and  prominency  in  their 
centre,  that  fits  them  to  grind  whatever  comes 
under  their  action  ;  these  plates  are  surrounded 
and  connected  by  a  cartilaginous  ligament  by 
which  they  are  moved.  It  is  supposed  that  such  a 
structure  is  necessary  to  the  existence  of  these 
mollusks ;  for  they  are  exceedingly  voracious, 
as  is  evident  from  the  fact  that  the  animal  of 
Bulla  aperta  has  been  found  quite  distorted  from 

*  The  children  being  acquainted  with  the  words  rostrum 
and  bis,  will  see  at  once  the  derivation  of  this  word, 
t  Plate  II.  fig.  8. 


its  having  swallowed  entire  a  shell  nearly  equal 
in  size  to  itself;  not  unfrequently  shells  are 
found  in  their  gizzard,  reduced  to  a  powder, 
affording  ample  proof  that  it  unites  the  two 
offices  of  mastication  and  digestion. 

The  Bullae  are  not  furnished  with  an  oper- 
culum ;  indeed  to  many  of  the  species  it  would 
be  a  useless  appendage,  as  the  animal  extends 
beyond  the  shell,  and  cannot,  on  account  of  its 
gizzard  contract  itself  so  as  to  retire  within. 
The  marine  species  also  reside  in  deep  water, 
and  they  are  as  safe  there  from  crabs  and  other 
enemies  as  the  mollusks  who  live  near  the  shore, 
and  barricade  the  mouth  of  their  shells  with  their 

BULLA  Lignaria* 


Specific  Character.  Shell  oval,  thin,  brittle, 
semi-transparent,  yellowish  or  chesnut  brown, 
with  numerous  transverse  striae  of  a  light  colour 
approaching  to  white,  giving  it  some  resem- 
blance to  veined  wood  ;  sometimes  it  has  one  or 
two  oblique  bands ;  inside  white,  glossy  ;  aper- 
ture large,  extending  the  whole  length  of  the 
shell,  somewhat  contracted  towards  the  upper 
part ;  columellar  lip  smooth  ;  it  has  no  external 

*  Plate  II.  fig.  6. 


convolutions,  but  at  the  top  is  depressed,  and 
has  a  small  umbilicus  ;  it  is  usually  about  two 
inches  long,  and  one  and  a  quarter  broad  at  the 

This  is  one  of  the  Bullae  which  possess  a  giz- 
zard.* In  this  animal  it  consists  of  two  trian- 
gular, thin,  testaceous  plates  nearly  an  inch  in 
diameter,  and  another  of  an  elongated  semi- 
cylindrical  form.  These  plates  are  connected 
together  by  a  tough  yellowish  ligament  ;  and 
form  a  most  powerful  digestive  organ  ;  when  the 
animal  has  been  dissected,  there  have  been  found 
in  or  near  this  gizzard,  numerous  specimens  of 
the  smaller  testacea,  with  their  shells  reduced 
completely  to  a  powder. 

This  is  the  largest  species  of  the  British 

BULL  A  Fontinalis^ 


Specific  Character.  Shell  sinistral,  having  four 
or  five  reversed  volutions,  glossy,  pellucid,]:  and 
of  a  light  horn  colour ;  the  body  whorl  is  large ; 
the  others  are  very  small,  and  not  much  pro- 
duced ;  aperture  oval  oblong,  three  fourths  of 
the  length  of  the  shell.  Old  specimens  are 

*  Plate  II.  fig.  7.  +  Plate  II.  fig.  9. 

J  Pellucid,  so  clear  that  the  light  is  seen  through  it.  From 
Latin,  per  through,  and  lux  light. 


somewhat  striated,  and  rather  wrinkled  longitu- 
dinally, with  two  or  three  faint  tranverse  ridges 
on  the  body  whorl.  Length  in  the  largest 
specimens,  half  an  inch,  breadth  a  quarter. 

This  is  a  British  species,  not  unfrequently 
found  in  stagnant  pools  and  running  waters,  upon 
the  under  side  of  the  leaves  of  aquatic  plants. 

The  animal  is  of  a  light  yellowish  colour,  has 
two  long  setaceous*  tentacula,  with  two  black 
eyes  placed  underneath  at  their  base.  When  in 
motion,  it  covers  great  part  of  the  shell  with  a 
transparent  membrane,  scarcely  perceptible  to 
the  naked  eye. 

It  has  very  considerable  powers  of  locomotion, 
and  transports  itself  with  the  shell  downwards, 
by  adhering  to  the  surface  of  the  water,  crawling 
over  it  with  as  much  apparent  ease  as  if  it  were 
on  a  solid  body.  It  can  also  let  itself  down 
gradually  by  a  thread  which  it  affixes  to  the 
surface  of  the  water,  as  a  caterpillar  attaches 
itself  to  the  branch  of  a  tree ;  it  is  the  only 
animal  that  is  known  to  be  capable  of  thus  sus- 
pending itself  under  water.  It  has  also  the 
power  of  throwing  its  shell  about  in  an  extraor- 
dinary manner,  whilst  it  keeps  its  body  fixed  by 
its  foot  ;  it  probably  resorts  to  this  singular 
habit  either  in  self-defence,  or  to  remove  the 
little  aquatic  animals  with  which  it  is  tormented. 

*  Setaceous— "bristle  shaped,  from  Latin  seta,  a  bristle. 


Genus.— VOUJT  A*— Plural,  Volutes. 


Generic  Character.  Shell  univalve,  spirally 
convoluted  ;  shape  suboval ;  aperture  narrow, 
longitudinal,  generally  effuse  at  the  base  ;  having 
sometimes  a  dorsal  notch  ;  columella  has  oblique 
plaits,  varying  in  size  and  number. 


This  genus  contains  shells  highly  valued  for 
the  beauty  of  their  colours,  and  the  brightness 
of  their  natural  polish.  They  vary  considerably 
in  their  appearance.  Some  have  the  aperture 
entire ;  in  others  it  is  effuse,  terminated  by  a 
notch,  or  produced  into  a  canal ;  the  distinctive 
mark  however  by  which  they  may  be  immedi- 
ately recognised  is  the  plicated  t  columellar  lip. 
It  is  supposed  that  the  animals  inhabiting  such 
variously  formed  shells,  must  also  be  very  differ- 
ent, since  it  is  found  that  the  abode  of  a 
mollusk  is  invariably  suited  to  its  conformation 
and  habits.  There  are  but  very  few  British 
species  of  this  genus,  and  even  these  are  doubtful. 

*  Plate  II.  figures  10,  11. 
•f  Derived  from  Latin  plica,  a  fold. 


The  term  Voluta  signifies  rolled  up  cylin- 

One  large  family  has  been  separated  by  modern 
conchologists  from  the  Volutes,  and  formed 
into  a  distinct  genus  called  Oliva,  composed 
principally  of  the  Voluta  Oliva*  of  Linnaeus. 
These  shells  are  of  a  cylindrical  form,  have  a 
short  spire,  and  the  aperture  notched  at  the  base. 
They  are  easily  distinguished  from  all  other 
Volutes,  by  having  their  whorls  separated  by  a 
channel.  Their  surface  displays  a  fine  polish, 
and  many  of  them  are  beautifully  coloured.  It 
appears  that  the  Olives  are  formed,  like  the 
Cowries,  of  two  coatings  of  testaceous  matter  ; 
when  the  upper  one  is  artificially  removed,  that 
underneath  often  displays  most  beautiful  tints. 
They  are  found  in  hot  climates.  The  animals 
which  inhabit  them,  breathe  only  water,  which 
they  inhale  by  means  of  a  tube  situated  under 
the  head,  and  fitting  into  the  dorsal  notch. 

Another  large  family  of  Volutes  are  called 
Mitres,  from  their  resemblance  to  the  insignia 
of  clerical  dignity.  These  are  now  arranged  in 
a  distinct  genus  bearing  the  name  Mitra.  Their 
form  is  more  elongated  than  that  of  their  con- 
geners, being  f  turretedor  fusiform,  and  the  apex 
very  pointed.  They  are  also  characterized  by  the 
gradual  decrease  in  the  size  of  the  collumellar 
folds  as  they  approach  the  base.  These  shells 

*  Plate  II.  fig.  10. 

t  The  whorls  gradually  decreasing,  the  length  of  such  shells 
greatly  exceeds  their  breadth. 


are  as  much  admired  for  the  brightness  and 
variety  of  their  colours  as  for  the  elegance  of  their 
form.  They  are  found  in  the  seas  of  hot  cli- 
mates. The  natives  of  the  Island  of  Tanna  fix 
them  into  handles  and  use  them  for  hatchets. 
The  Voluta  Epicopalis  or  Bishop's  Mitre,*  is 
the  type  of  this  family.  It  is  white,  marked 
with  distinct  orange  spots.  It  is  frequently 
found  in  India.  Its  inhabitant  is  said  to  be  of  a 
poisonous  nature,  and  to  wound  with  its  pointed 
proboscis  any  offender  who  ventures  to  touch  it. 

VOLUTA  Musica. 


Specific  Character.  Shell  oval,  with  pointed 
tubercles  on  the  whorls ;  aperture  emarginate,f 
columella  with  eight  plaits;  outer  lip  smooth 
and  thick  ;  shell  two  or  three  inches  in  length, 
colour  white  or  buff ;  it  is  remarkable  for  its 
dark  markings,  arranged  like  a  stave  in  music 
in  parallel  lines,  upon  which  are  spots  resembling 
the  notes;  from  this  appearance  it  derives  its 

*  Plate  II.  fig.  11. 

t  Emarginate,  notched,   or  having  the  margin  excavated 
by  a  sinus. 


VOLUTA  Pyrum. 


Specific  Character.  Shell  pear-shaped,  ponde- 
rous, smooth,  canaliculated,  striated,  and  slightly 
nodulous  transversely;  spire  acute;  columellar 
lip  with  three  plaits;  colour  dirty  white;  the 
young  shells  are  yellowish,  and  have  irregular 
transverse  rows  of  dark  spots.  The  size  of  the 
perfect  shell  is  about  five  inches  long,  and  about 
half  as  broad. 

The  reversed  shells  of  this  species  are  held 
sacred  in  China,  where  a  great  price  is  given  for 
them ;  they  are  kept  in  pagodas  by  the  priests, 
who  on  certain  occasions  administer  medicine  to 
the  sick  out  of  them,  they  also  use  them  to  anoint 
the  Emperor  at  his  ^coronation.  They  are  often 
curiously  ornamented  with  carvings,  executed 
by  the  Indians,  who  use  them  for  drinking  cups. 

Genus.— BUCCINUM.*— PZwraZ,  Buccina. 


Generic  Character.     Shell  univalve,  spirally 
convoluted,  frequently  canaliculated ;  form  gib- 

*  Plate  III.  %  1,  2,  3,  4. 


bous ;  aperture  ovate,  effuse  at  the  base,  ending 
either  in  a  notch,  or  a  short  canal  abruptly 
curved  and  turning  to  the  left,  that  is,  from  the 
outer  lip  ;  columellar  lip  flattened. 


The  characters  which  distinguish  this  genus 
do  not  always  occur  in  each  species.  The  most 
invariable  mark  of  distinction  is  the  direction  of 
the  canal ;  and  should  this  fail,  as  is  the  case  in 
a  few  instances,  the  thick  gibbous  form  or  the 
flattened  columellar  lip  will  still  point  out  the 
proper  situation  of  the  shell  to  be  amongst  the 

One  division  of  this  genus  is  known  by  the 
common  name  of  Tuns  ;  their  scientific  name 
is  Dolium.  These  shells  are  thin,  brittle,  turbi- 
nate,  of  an  inflated  or  globular  form,  transversely 
ribbed,  the  aperture  is  large,  and  has  a  notch 
at  the  base.  The  type  is  the  Buccinum  Dolium.* 

Many  of  the  Buccina  are  called  Helmets, f 
and  are  distinguished  by  their  inflated,  turbinate 
form,  and  by  their  short  beak  abruptly  reflected  ; 
their  columellar  lip  is  thickened  and  spread  over 
the  body  whorl,  forming  a  flat  expansion  ;  their 
outer  lip  is  also  revolute,J  and  often  dentated  ;  § 

*  Plate  III.  fig.  1.  t  Plate  III.  fig.  3. 

$  Revolute,  rolled  back. 
§  Dentated :  toothed,  frpm  Latin,  dens,  a  tooth. 


their  spire  is  retuse  and  marked  at  intervals  by 
curved  ridges  which  are  the  permanent  margins 
of  the  former  apertures,  and  are  interesting,  as 
marking  clearly  the  various  stages  of  the  shell's 
increase.  The  Helmets  are  very  common,  and 
many  are  remarkable  on  account  of  their  size  and 
solidity.  One  species  (the  Buccinum  Cornutum) 
is  more  than  a  foot  in  length.  These  shells  are 
handsome  and  are  often  used  as  ornaments  in 
rooms.  They  are  found  mostly  in  topical  seas,  dis- 
tant from  the  shores,  in  sandy  bottoms  where 
the  animal  buries  itself  in  search  of  prey.  They 
form  the  modern  genus  Cassis. 

The  most  beautiful  shells  of  this  genus  are 
called  Harps ;  *  they  have  an  elegant  shape,  rich 
tints,  and  usually  a  glossy  surface ;  their  form 
is  oval,  spire  short,  aperture  large,  notched  at 
the  base,  the  inner  lip  is  spread  over  a  portion  of 
the  body  whorl,  the  outer  lip  is  thickened  and 
rolled  outwards.  The  animal  produces  this 
thickened  revolute  lip  at  different  periods  of  its 
growth,  thus  forming  a  number  of  elevated 
ridges  on  the  shell.  Such  marks  of  increase  are 
observable  in  many  other  marine  shells,  and  in 
a  few  land  species;  but  in  none  are  they  more 
numerous  than  in  the  Harps.  The  effect 
of  these  ribs  is  very  rich  and  pleasing.  The 
Harps  are  found  in  the  seas  of  hot  climates, 
particularly  near  the  Isle  of  France.  The  genus 
they  now  form  is  called  Harpa. 

*  Plate  III.  fig.  2. 
G  2 


Another  very  distinct  natural  group  of  this 
genus  consists  of  shells  called  Needle  Buc- 
cina,* a  term  which  indicates  their  subu- 
late form.  They  possess  the  characteristic 
mark  of  the  genus  in  the  notch  of  the  aperture 
slanting  towards  the  left,  though  their  pointed 
elongated  shape  gives  them  a  very  different  ap- 
pearance to  that  of  the  Buccina  in  general.  They 
are  now  arranged  in  a  genus  called  Terebra. 

The  name  given  to  this  genus  is  derived  from 
the  Latin  buccina,  a  trumpet,  and  it  is  very  proba- 
ble that  these  shells  furnished  the  first  idea  of  that 
instrument,  for  if  the  apex  be  pierced  or  broken 
off,  a  variety  of  sounds  may  be  produced  by 
blowing  into  it.  Triton,  the  fabled  trumpeter  of 
Neptune,  is  represented  with  one  of  these  shells 
in  his  hand,  when  he  is  supposed  to  be  calling  up 
the  river  deities  to  attend  their  monarch.  This 
kind  of  trumpet  is  still  used  by  the  Italian 
herdsmen  to  direct  the  movements  of  their  cattle. 
In  a  part  of  Wales  also  the  farmers  summon 
their  labourers  in  a  similar  manner,  and  the 
deep  and  sonorous  notes  thus  produced,  breaking 
in  upon  the  silence  of  those  mountainous  districts 
have  a  very  striking  effect.  In  Palestine  the 
bee  masters  enticed  their  bees  with  a  whistle 
made  by  means  of  some  shell,  (probably  a  Buc- 
cinum)  and  led  them  from  meadow  to  meadow 
to  collect  their  store  of  sweets.  Isaiah  seems  to 
refer  to  this  custom  when  he  prophecies  the  con- 

*  Plate  III.  fig.  4. 


quests  of  the  Assyrian  monarch.  "  And  it  shall 
come  to  pass  in  that  day  that  the  Lord  shall 
hiss  (or  whistle)  for  the  bee  that  is  in  the  land  of 
Assyria.  And  they  shall  come,  and  shall  rest 
all  of  them  in  the  desolate  valleys,  and  in  the 
holes  of  the  rock,  and  upon  all  thorns  and  upon 
all  bushes."  Isa.vii.  18,  19. 

Various  species  of  turbinated  shells,  chiefly 
of  the  Buccinum  or  Whelk  tribe,  are  picked  up 
on  the  shores  of  the  Isle  of  Wight.  They  are 
found  tenanted  not  by  their  natural  inhabitants, 
who  love  the  deep  recesses  of  the  ocean,  but  by 
a  species  of  Crab  called  the  Bernard,  or  Hermit 
Crab.  This  creature  curiously  exhibits  the 
wonderful  operations  of  animal  instinct,  whilst 
he  exemplifies  in  a  striking  manner  the  resources 
of  a  compensatory  Providence.  The  hinder  part 
of  his  body  is  tender  and  naked,  unprotected 
by  that  shelly  covering  which  guards  his  head 
and  anterior  extremities  ;  he  would  therefore  be 
peculiarly  liable  to  injuries  were  he  not  endowed 
with  a  foresight  that  directs  him  most  inge- 
niously to  provide  against  any  accident.  This 
he  effects  by  seeking  for  the  roomy  cavity  of 
some  forsaken  Whelk,  and  wriggling  himself 
into  it,  he  maintains  his  hold  by  means  of  a 
hooked  claw,  which  he  fastens  to  any  projection 
in  the  shell,  while  his  head  and  front  claws  hang 
out  at  the  aperture.  Thus  secure,  this  little  crab 
continues  till  increased  in  size  he  is  compelled  to 
abandon  his  retreat  and  seek  for  a  tenement  of  more 
ample  dimensions  ;  at  such  times  he  maybe  seen 


traversing  the  sands,  searching  with  patience  and 
assiduity  for  another  abode,  and  examining  each 
empty  shell,  till  he  meets  with  one  better  suited 



Specific  Character.  Shell  oval,  turbinate  with 
longitudinal,  acute,  and  curved  varices;  mouth 
expanding,  notched  at  the  base  ;  outer  lip  re- 
volute  ;  collumellar  lip  smooth,  flattened  ;  va- 
riously marbled  or  banded  with  fawn  colour  or 
reddish  brown  ;  size  from  two  to  three  inches 
long,  and  nearly  two-thirds  as  broad. 

There  are  several  varieties  of  this  species, 
which  is  much  distinguished  for  its  beauty. 
They  are  found  principally  in  the  Indian  ocean, 
also  in  the  seas  of  hot  climates.  They  are 
furnished  with  a  horny  operculum. 

BUCCINUM  Undulatum. 


Specific  Character.     Shell   thick  and  coarse, 
with  seven  or  eight  ventricose  whorls,  having 

*  Plate  III.  figure  2. 

undulating  *  ribs  both  transversely  and  longi- 
tudinally striated ;  varies  in  colour  from  dirty 
white  to  chesnut  brown ;  size  from  two  to  five 
inches  long,  and  more  than  half  as  broad. 

There  are  scarcely  any  of  our  shores  which  do 
not  produce  this  shell.  It  is  commonly  taken 
in  dredging  by  fishermen,  who  either  use  the 
animal  for  bait,  or  destroy  it,  under  the  suppo- 
sition that  it  is  very  destructive  to  a  large  species 
of  scallop,  insinuating  its  tail,  as  they  term  the 
trunk,  into  the  shell,  and  killing  the  inhabitant 
for  food.  The  old  shells  are  frequently  covered 
with  a  brown  epidermis,  or  rough  extraneous 

The  animal  has  two  conical  tentacula  bearing 
eyes  at  their  base,  a  short  foot,  to  which  is 
attached  a  horny  operculum,  and  a  long  trunk 
that  issues  through  the  notch  at  the  base  of  the 

BUCCINUM    Lapittus. 


Specific  Character.  Shell  ovate,  thick,  with 
five  or  six  whorls  more  or  less  striated  longitu- 
dinally, and  transversely  crossed  with  finer 
irregular  striae  ;  apex,  small,  pointed;  aperture 
oval ;  outer  lip  waved  or  denticulated ;  it  is 
usually  of  an  uniform  dirty  white,  or  yellowish 

*  Undulating :  wavy,  from  the  Latin  undul  a,  a  small  wave. 


colour,  sometimes  banded  with  brown  or  yellow. 
Length  rarely  exceeds  two  inches,  breadth  one. 

The  animal  that  inhabits  this  shell  has  two 
slender  tentacula  bearing  eyes  about  half  way 
up  on  the  outside,  the  ends  of  the  tentacula  as 
far  as  the  eyes  are  retractile  *  like  those  of  snails. 
Its  mantle  forms  a  tube  through  which  it 
breathes  ;  it  has  a  foot  with  a  horny  operculum. 
Near  to  its  head,  and  lying  in  a  little  furrow,  is 
a  white  vein  which  yields  a  beautiful  purple  tint, 
supposed  to  be  that  so  long  celebrated  as  the 
Tyrian  dye.  In  order  to  obtain  this  colour,  the 
vein  is  laid  open  with  a  needle,  and  is  found  to 
contain  a  tenacious  yellow  matter  like  cream. 
As  soon  as  this  fluid  is  put  on  any  substance,  as 
silk,  linen,  &c.  and  exposed  to  the  air,  the  yellow 
assumes  a  brighter  hue,  but  speedily  turns  to  pale 
green,  then  gradually  becoming  darker,  until  it 
has  obtained  a  blue  cast,  and  from  that  it 
changes  to  a  purplish  red,  more  or  less  deep 
according  to  the  quantity  used.  The  succession 
of  the  tints  is  accelerated  by  exposure  to  the  rays 
of  the  sun.  The  stain  given  by  this  animal  fluid 
seems  to  be  indelible,  bidding  defiance  to  every 
chemical  process  to  obliterate  it,  and  it  might 
therefore  be  most  advantageously  used  as  a 
kind  of  marking  ink. 

The  Buccinum  Lapillus  is  one  of  the  most 
common  shells  upon  our  coasts,  adhering  to 
rocks  quite  up  to  high  water  mark. 

*  Retractile,  capable  of  being  drawn  back,  from  the  Latin 
re  back,  and  tract  us  drawn. 


BUCCINUM  Suhulatum.* 


Specific  Character.  Shell  turreted,  subulate, 
smooth  :  colour  white,  tinged  with  yellow,  red, 
or  brown,  and  marked  on  the  body  whorl  with 
three  rows  of  squarish,  dark,  ferruginousf  spots; 
the  shell  is  from  three  to  six  inches  long,  and 
the  breadth  scarcely  exceeds  one  eighth  of  the 

Genus.— STROMBUS.J  Plural,  Strombi. 


Generic  Character.  Shell  univalve,  spirally 
convoluted,  canaliculated  ;  form  suboval ;  aper- 
ture more  or  less  dilated,  ending  in  a  beak 
turning  to  the  right,  that  is,  towards  the  outer 
lip ;  the  outer  lip  usually  expanding  into  a  kind 
of  wing,  with  a  sinus  near  the  base. 


The  remarkable  peculiarity  in  the  shells  of  this 
genus  is  their  propensity  to  have  their  outer  lip 
expanded  into  a  wing-like  projection ;  from  this 

*  Plate  III,  figure  4. 

+  Ferruginous,  of  the  colour  of  iron  rust,  from  the  Latin 
ferrug  0,  rust.  J  Plate  III.  figure  5. 


circumstance  they  are  sometimes  called  the 
Alatae  *  or  winged  shells.  In  some  species  this 
expansion  is  lobed,  in  others  it  is  divided  into 
curious  digitations  f  or  claws,  giving  the  shells 
a  resemblance  to  spiders  or  scorpions,  whence 
they  have  received  their  specific  names.  Some 
are  remarkable  for  a  lengthened  spire,  and  very 
much  resemble  in  form  the  Needle  Buccinum  ; 
these  now  form  the  genus  Terebra. 

The  distinguishing  marks  of  Strombi  are  the 
sinus  in  the  outer  lip  near  the  base,  and  the  posi- 
tion of  the  beak.  Like  the  Cypraeae,  they  vary  so 
considerably  in  their  different  stages  of  growth, 
that  the  juvenile  specimens  are  scarcely  to  be 
recognised  as  belonging  to  this  genus  :  at  an  early 
period  the  outer  lip  is  not  expanded,  and  there 
are  no  traces  of  claws  ;  subsequently  the  wing 
spreads  out,  and  the  claws  appear  as  short 
open  spouts ;  and  when  the  shell  arrives  at  its 
full  size,  these  become  solid  hornlike  projections, 
often  very  long  and  curiously  curved. 

There  are  not  more  than  two  or  three  species 
of  the  Strombus  found  on  our  coasts. 

The  inhabitant  is  little  known,  but  it  is  sup- 
posed from  its  second  sinus  or  notch,  and  its 
curious  digitations,  that  there  must  be  some 
peculiar  circumstances  in  its  construction  and 

*  Alatae  winged,  from  the  Latin  ala,  a  wing, 
f  Digitations,  projections  in  the  form  of  fingers,  from  the 
Latin  digit  us,  a  finger. 


STROMBUS  Pes  Pelicani* 

Specific  Character.  Shell  turreted,  finely 
striated  transversely  ;  spire  tapering  to  a  fine 
point  with  ten  tuberculated  convolutions;  the 
body  whorl  has  two  rows  of  smaller  tubercles 
beneath  the  larger  ones ;  outer  lip  much  ex- 
panded, four-clawed,  the  upper  claw  extending 
up  the  spire,  the  lower  one  forming  the  beak ; 
the  two  middle  ones  are  ribbed  along  the  back 
in  a  continued  line  from  the  rows  of  tubercles, 
and  underneath  is  a  corresponding  groove.  The 
shell  is  of  a  pale  brownish  flesh  colour.  Length 
nearly  two  inches. 

The  Strombus  Pes  Pelicani  is  subject  to 
great  variations  in  the  different  stages  of  its 
growth.  In  young  shells  f  the  outer  lip  has  not 
assumed  its  peculiar  form  ;  it  first  gradually 
expands,  then  the  claws  appear,  and  finally  it 
becomes  digitated.  Shells  are  found  in  all  the 
intervening  gradations  between  the  young  and 
the  adult  specimen. 

This  species  is  rather  common  on  many  of  the 
coasts  of  Great  Britain,  it  is  chiefly  met  with  on 
sandy  shores. 

*  Plate  III.  figure  5.  f  Plate  III.  figure  6. 


STROMBUS  Ckbragra* 


Specific  Character.  Shell  ovate,  turreted; 
spire  short,  tuberculated ;  outer  lip  having  six 
strong  curved  claws,  the  sinus  not  immediately 
at  the  base ;  mouth  striated ;  colour  white 
mottled  with  brown ;  lips  orange  colour  with 
black  and  white  stripes;  outside  generally 
coated  with  a  thin  horny  epidermis  ;  size  about 
five  inches  long  and  three  broad  not  including 
the  claws,  which  are  from  two  to  three  inches 
long,  the  upper  and  lower  ones  curved  in 
opposite  directions. 

This  Strombus  also  exhibits  a  very  different 
appearance  at  its  various  periods  of  growth. 

Genus.— MUREX.*— PfcwaZ,  Murices. 


Generic  Character.     Shell  univalve,  spirally 
convoluted,    canaliculated,    rough  with   spines, 

*  Signifying,  savage  claw,  from  the  Greek  words  x*l§» 
(cheir)  hand,  and  ay  go,,  (agra)  fierce  or  savage. 

•f  Probably  named  from  the  Latin,  murex,  the  primary 
signification  of  which  seems  to  have  been  the  sharp  point  of  a 
rock.  Plate  IV.  figure  1,  2,  3. 


tubercles,  foliations,  or  varices ;  aperture  oval 
ending  in  a  beak,  either  straight  or  turned 
backwards.  Some  of  the  species  are  remarka- 
ble for  the  great  length  of  the  beak. 


The  very  great  variety  which  occurs  in  the 
shells  of  this  genus  has  caused  them  to  be  ar- 
ranged under  several  divisions ;  but  the  mark 
by  which  a  Murex,  according  to  the  Linnaean 
definition,  may  be  easily  recognised,  is  the  oval 
shape  of  the  mouth  ;  this  being  preserved  even 
when  the  aperture  is  terminated  by  a  beak,  as 
instead  of  gradually  contracting,  it  abruptly 
opens  into  a  canal.  Besides  this  regularity  in 
the  outline  of  the  aperture,  another  distinctive 
mark  is  that  the  beak  neither  inclines  to  the 
right  nor  to  the  left* 

The  Murices  are  in  general  of  an  irregular 
form,  arising  from  their  surfaces  being  covered 
either  with  spines,  tubercles,  varices,  or  folia- 
tions ;  and  from  the  rock-like  and  rugged  ap- 
pearance thus  occasioned  they  derive  their  desig- 
nation. Some  of  the  shells  of  this  genus  are 
remarkable  for  the  singular  extension  of  their 

Many  of  the  Murices  are  distinguished  by 
their  thick  protuberent  rounded  varices.  These 
shells  have  been  divided  into  different  genera 


according  to  the  arrangement  of  these  ornaments. 
In  one  division  the  shells  are  distinguished  by 
having  two  varices  in  each  whorl,  which  are  con- 
tinued in  a  longitudinal  series  on  each  side  up 
to  the  apex,  giving  them  a  flattened  appear- 
ance on  the  front  and  back  ;  the  genus  which 
they  now  constitute  is  called  Ranella*  Frog, 
from  the  resemblance  of  the  shells  to  that  animal. 

The  shells  of  another  division  f  are  distin- 
guished by  three  rows  of  varices,  sometimes  ex- 
panding into  elegant  foliations  or  lengthened 
spines,  these  varices  are  so  arranged  that  they 
form  three  longitudinal  raised  lines  taking  rather 
an  oblique  inclination  towards  the  apex.  It  is 
evident  that  the  habits  of  the  mollusca  of  these 
two  sets  of  shells  must  be  different,  for  the  situa- 
tion of  the  varices  of  the  latter  proves  that  a 
smaller  portion  is  added  to  the  abode  at  each 
epoch  of  its  growth  than  in  the  Ranella. 

A  third  division  J  of  this  genus  includes  shells 
ornamented  by  varices,  not  disposed  in  a  con- 
tinued series  as  in  the  other  two  classes.  This 
difference  in  the  disposition  of  these  protuber- 
ances is  occasioned  by  the  piece  which  the 
animal  adds  to  its  shell  being  more  than  half  a 
volution.  The  varices  are  consequently  few, 
and  appear  scattered  over  the  shell. 

*  Plate  IV.  fig.  2.  t  Plate  IV.  fig.  1. 

$  Plate  IV.  fig.  3. 

MUREX—  flOCfiT  SHELL.  95 


Specific  Character.  Shell  oval  with  three 
foliated  varices  ;  beak  short  and  truncated  ;  the 
colour  of  this  shell  varies  greatly  ;  it  is  some- 
times of  an  uniform  whiteness,  sometimes  pale 
yellow,  brown,  pale  red,  nearly  black,  and 
sometimes  the  whorls  are  of  one  of  these  colours, 
and  the  foliations  of  another.  Its  dimensions 
also  differ  greatly;  it  varies  from  two  to  five 
inches,  and  is  about  half  as  broad. 

There  is  a  circumstance  of  unusual  interest 
to  be  observed  in  the  manner  in  which  this  ani- 
mal increases  the  size  of  its  shell,  and  which 
shews  most  admirably  the  regularity  and  beauty 
of  the  laws  of  nature,  and  directs  the  mind  to 
the  contemplation  of  the  wisdom  and  power  of 
the  Creator,  who  alone  could  teach  these  little 
animals  how  to  construct  an  habitation  so  per- 
fectly adapted  to  their  circumstances  and  situa- 
tion. It  will  be  observed  that  each  periodical 
increase  of  these  shells  consists  of  a  piece  which 
surrounds  about  a  third  part  of  the  last  volution 
already  formed,  which  portion  is  terminated  in 
this  species  by  a  foliated,  in  some  by  a  spinous 
varix,  it  is  obvious  that  these  foliations  or  spines 
must  be  in  the  way  of  the  future  increase  of  the 

*  Plate  IV.  fig.  1. 


shells,  unless  they  could  be  removed  from  that 
part  which  it  is  intended  to  cover ;  the  animal 
therefore  is  furnished  with  the  means,  perhaps 
by  a  solvent  liquid,  of  eating  away  the  lower 
part  of  these  projections;  so  that  they  become 
detached  and  fall  off  by  the  time  that  he  is 
ready  to  form  his  new  inner  lip  upon  the  space 
which  they  occupy,  thus  forming  a  comparatively 
smooth  and  even  surface  on  which  he  is  to  spread 
the  testaceous  matter,  of  which  the  addition  to 
his  building  is  composed.* 

It  is  principally  in  this  genus  that  are  found 
the  shells  which  yielded  the  celebrated  Tyrian 
dye,  they  were  thence  called  Purpurae.  An  ex- 
pression of  Virgil  implies  that  it  was  extracted 
from  the  animals  of  this  genus  in  his  time  ; 
He  says,  "  glowing  with  Tyrian  Murex."  The 
Tyrians  were  the  most  successful  among  the 
ancients  in  preparing  and  using  this  celebrated 
colour.  The  Mediterranean  supplied  them  with 
the  mollusks  in  abundance,  and  in  order  to  pro- 
duce the  tint  that  was  in  highest  estimation,  a 
bath  of  the  liquid  extracted  from  the  animal  of 
the  Murex  was  prepared  :  in  this  they  steeped 
the  wool  for  a  certain  time,  and  when  taken  out 
they  immersed  it  in  another  boiler,  which  con- 
tained an  extract  from  the  Buccinum  alone. 
Wool  which  had  been  subjected  to  this  double 
process  was  so  highly  valued,  that  in  the  reign 
of  Augustus  each  pound  of  it  sold  for  about 

*  Sowerby's  Genera  of  Recent  and  Fossil  Shells. 


£36;  this  enormous  price  is  not  to  be  won- 
dered at,  as  only  a  single  drop  of  the  colouring 
fluid  is  afforded  by  each  animal. 

This  beautiful  and  precious  colour  was  held 
in  the  highest  estimation  by  the  ancients, 
and  in  some  countries  it  was  consecrated  to 
sacred  purposes.  Moses,  under  divine  instruc- 
tion, used  purple  stuffs  for  the  furniture  of  the 
tabernacle,  and  for  the  dress  of  the  high  priests. 

The  Babylonians  arrayed  their  idols  in  robes 
of  splendid  purple  ;  and  such  indeed  was  the 
practice  of  the  Pagans  in  general,  many  of  whom 
superstitiously  believed  that  this  dye  had  a 
peculiar  virtue,  and  was  capable  of  appeasing 
the  wrath  of  their  pretended  gods. 

Purple  robes  were  also  characteristic  of  regal 
dignity,  and  by  an  imperial  decree  in  Rome, 
they  were  entirely  restricted  to  the  use  of  the 
emperor,  the  penalty  of  death  being  inflicted  on 
any  who  dared  to  appear  in  habiliments  of  this 
hue.  The  language  of  the  day  shews  how  ex- 
clusively this  colour  is  appropriated  to  the  empe- 
rors, for  "  to  assume  the  purple,"  signified  the 
being  elevated  to  the  Imperial  Throne. 

Several  different  accounts  are  given  of  the 
discovery  of  this  dye  ;  but  they  all  seem  to  have 
originated  in  the  simple  fact,  that  a  dog  having 
broken  one  of  the  shells,  stained  his  mouth  with 
the  colour,  which  excited  the  attention  of  his 
owner,  and  led  to  an  examination  of  the  cause. 

The  vast  heaps  of  fragments  of  shells  found 
about  Tarentum,  are  supposed  to  be  those  from 


which  the  celebrated  dye  was  extracted,  and 
seem  to  indicate  that  place  as  one  where  it  was 
prepared  ;  it  has  not  been  ascertained  to  what 
species  these  shells  belong. 

MUREX  TriMus. 


Specific  Character.  Shell  subovate,  with  three 
spinous  varices  :  spines  continued  to  the  extrem- 
ity of  the  beak,  which  is  long ;  between  the 
varices  the  shell  is  transversely  ribbed  and 
slightly  nodulous :  the  colour  is  dirty  white, 
or  pale  brownish  white  ;  the  shell  is  about  three 
or  four  inches  in  length,  of  which  the  subulate 
beak  occupies  the  larger  part ;  the  breadth  of 
the  body  whorl  is  about  an  inch  and  a  quarter, 
or  an  inch  and  a  half. 

This  shell  is  found  in  the  Asiatic  and  American 
seas,  also  in  the  Red  Sea.  It  was  first  discovered 
by  a  singular  accident.  A  diver  feeling  a  sharp 
pain  from  something  having  pierced  his  foot,  and 
apprehending  that  it  might  proceed  from  the  bite 
of  some  venomous  animal,  immediately  gave 
the  signal  to  be  drawn  up,  when  he  perceived 
that  it  arose  from  one  of  these  shells,  the  thorns 
of  which  had  entered  his  flesh. 


MUREX  Tritonia. 

Specific  Character.  Shell  ventricose,  with 
alternate  varices,  and  slightly  elevated  transverse 
ribs,  the  interstices  striated ;  the  whorls  cre- 
nated  *  at  the  suture ;  columellar  lip  grooved  ; 
beak  short  and  ascending;  colour  whitish,  orna- 
mented on  the  ribs  with  parallel  curved  reddish 
brown  spots,  which  are  shaded  off  towards  each 
other  ;  columellar  lip  striped  with  dark  brown  ; 
the  length  is  a  foot,  sometimes  sixteen  inches, 
and  the  breadth  about  half  as  much. 

It  inhabits  the  Asiatic  seas,  and  those  of  the 
Torrid  zone  in  general.  It  is  used  by  the 
natives  of  New  Zealand  as  a  musical  instrument, 
and  by  the  Africans  as  a  military  trumpet.  It 
is  supposed  to  be  the  shell  intended  by  Ovid, 
when  he  describes  the  waters  of  the  deluge 
retiring  on  the  sound  of  the  trumpet  of  Triton. 

Genus— TROCHUS  ^—Plural,  TrocU. 


Generic  Character.     Shell  univalve,  spirally 

*  Crenated,   being  notched,   from  the  Latin  cren  a,  the 
notch  of  an  arrow. 

t  Plate  IV.  figures  4,  5,  6. 
H  2 


convoluted  ;  form  more  or  less  conical ;  aperture 
entire,  quadrangular,  sometimes  approaching  to 
round,  generally  wider  than  it  is  long  ;  margins 
separated ;  columella  oblique. 


Many  of  the  Trochi  so  nearly  resemble  the 
shells  in  the  following  genus  Turbo,  that  it  is 
often  difficult  to  discriminate  between  them.  The 
character  by  which  the  former  are  most  readily 
known,  is  the  angular  contour  of  the  mouth. 
Their  true  form  is  that  of  a  pointed  cone,  capa- 
ble of  standing  nearly  perpendicular,  or  but  little 
inclined  on  its  base.  Some  of  these  erect  shells* 
have  their  columella  umbilicated,  othersf  are 
imperforate.  A  few  of  the  Trochi  are  elongated  J 
resembling  in  form  the  Needle  Buccinum ;  these 
have  an  exserted  columella,  and  when  placed  on 
their  base,  fall  on  one  side.  These  latter  are 
now  arranged  in  the  genus  Pyramidella. 

Many  of  the  shells  of  this  genus  have  their 
outside  rough  with  tubercles,  and  many  are 
covered  with  a  thick  epidermis,  on  the  removal 
of  which  a  bright  surface  appears,  shining  with 
iridescent  colours.  The  animals  which  inhabit 
the  Trochi  have  no  proboscis,  but  a  mouth 
armed  with  two  jaws,  and  thence  it  is  concluded 

*  Plate  IV.  figure  5.  f  Plate  IV.  figure  4. 

£  Plate  IV.  fig  6. 


that  they  feed  upon  vegetables ;  the  shell  has 
neither  notch  nor  canal,  and  the  mollusk  no 

TROCHUS  Perspective* 


Specific  Character.  Shell  conical ;  umbilica- 
ted ;  the  umbilicus  large,  funnel-shaped,  round 
which  the  whorls  wind  spirally,  having  a  cre- 
nated  margin;  aperture  nearly  quadrangular; 
shell  flat  underneath,  longitudinally  and  trans- 
versely striated  ;  colour  greyish,  beautifully 
variegated  with  ochrous  brown  spots. 

This  shell  is  the  type  of  the  modern  genus 
Solarium.  It  inhabits  the  shores  of  Asia :  fre- 
quent about  Alexandria. 

TROCHUS  Cvnchyliopkorus. 


Specific  Character.  Shell  conical,  coarse, 
obtusely  plaited  ;  whorls  imbricated,!  base  con- 
cave ;  colour  brownish  white ;  size  an  inch  and  a 
half  long,  and  an  inch  and  three  quarters  broad. 

It  is  a  singular  fact  in  the  natural  history  of 

*  Plate  IV.  figure  5. 
t  Imbricated,  tiled,  from  the  Latin  imbrex,  a  tile. 


this  shell,  that  it  accumulates,  during  its  forma- 
tion, different  foreign  substances,  and  is  often 
found  covered  with  stones,  coral,  small  shells, 
and  fragments  of  shells;  on  account  of  this 
curious  property,  it  has  acquired  the  name  of  the 
Carrier.  It  has  not  been  ascertained  how  this 
animal,  during  the  formation  of  its  shell,  collects 
these  various  substances;  probably  some  very 
tenacious  matter  is  combined  with  its  calcareous 
secretions,  so  that,  whatever  comes  in  contact 
with  it  before  it  is  hardened,  adheres  to  its 

Genus— TURBO*— Plural,  Turbines. 


Generic  Character.  Shell  univalve,  spirally 
convoluted,  solid ;  shape  more  or  less  conical ; 
aperture  entire,  contracted,  orbicular. 


The  shells  of  this  and  the  preceding  genus 
are  often  so  similar,  that  it  is  difficult  to  define 

*  Plate  IV.  figures  7,  8. 


the  boundaries  by  which  they  are  separated  ;  the 
mouths  of  the  Trochi  gradually  losing  the 
angular,  and  assuming  the  orbicular  form  ; 
whilst  many  species  of  the  Turbines  exhibit  a 
very  imperfectly  circular  aperture.*  Both  names 
also  imply  any  thing  that  whirls  round  ;  and  the 
shells  in  each  genus  agree  in  their  conical  form, 
and  in  shewing  no  indication  of  an  increase  in 
growth,  after  the  first  formation.  Besides,  this 
general  resemblance  in  their  appearance,  the 
animals  are  nearly  allied  in  their  habits.  The 
marine  species  are  found  on  rocks  and  craggy 
shores,  or  on  the  sand,  when  detached  by  *a 
storm  from  their  customary  abode. 

There  are  several  species  of  Needle  or  Screw- 
shell  among  the  Turbines ;  they  are  distinguished 
by  their  circular  mouth,  from  those  of  a  similar 
form  in  other  genera ;  their  shape  is  that  of  a 
well-proportioned  spire,  formed  by  thirty  or 
forty  whorls,  gradually  tapering  from  the  base 
to  the  apex,  and  terminating  in  a  fine  point. 
There  are  upwards  of  seventy  species  of  Turbines 
among  British  shells,  and  several  of  them  are 
terrestrial.  t  One  called  Turbo  Fasciatus,  is 
found  so  abundantly  in  a  part  of  Cornwall,  that 
it  is  impossible  to  take  a  step  without  crushiing 
numbers.  It  is  the  prevailing  opinion  that  they 
contribute  much  to  fatten  sheep ;  they  spread 
themselves  over  the  plain  and  hill  near  Whitsand 
Bay,  Cornwall,  and  the  sheep  which  browse  on 

*  Turbo,  the  Latin  for  a  whirlwind  ;  trochus,  a  top. 


the  short  herbage,  must  devour  a  prodigious 
quantity  of  these  mollusks,  which  early  in  the 
morning  ascend  the  short  blades  in  quest  of  food. 
Some  very  small  Turbines,  are  found  abundantly 
on  old  walls  amidst  moss. 

TURBO  Littoreus* 


Specific  Character.  Shell  strong,  sub-oval  ; 
body- whorl  large,  the  others,  four  or  five  in 
number,  small  and  nearly  flat,  separated  only  by 
a  fine  line ;  aperture  suborbicular,  outer  lip 
thin,  inner  flat  and  thick.  When  full  grown, 
this  shell  is  nearly  smooth  and  of  an  uniform 
brownish  colour,  but  the  younger  shells  are  more 
distinctly  striated  and  variously  marked  with 
purple,  white,  yellow,  or  red  bands  ;  size,  about 
three  quarters  of  an  inch  long,  and  nearly 
equally  broad. 

The  Periwinkle  is  extremely  abundant  on  the 
shores  of  Great  Britain  ;  it  is  often  sold  in  our 
seaport  towns,  and  when  boiled,  eaten  by  the  lower 
classes.  It  is  found  on  rocks  usually  above  low 
water  mark.  The  Swedish  peasants  affirm,  that 
when  the  animals  of  this  species  ascend  the  rocks, 
it  is  a  sure  sign  of  an  approaching  storm,  for  that, 
prompted  by  instinct,  they  thus  place  themselves 

*  Littoreus  is  derived  from  the  Latin  word  littus,  a  shore. 
The  littoral  species  are  those  which  burrow  in  the  sand,  or 
adhere  to  the  rocks  when  left  dry  by  the  receding  tide. 


out  of  the  reach  of  the  dashing  of  the  waves  ;  and 
on  the  contrary,  that  when  they  make  their  de- 
scent into  the  sand,  is  is  an  indication  of  a  calm. 
The  mollusk  of  the  Periwinkle  is  striped 
with  black ;  it  has  two  setaceous  tentacula  annu- 
lated,*  or  streaked  transversely  with  black  ;  the 
eyes  are  at  the  base  of  the  tentacula  and  are 
very  prominent. 

TURBO  Scalaris.^ 


Specific  Character.  Shell  turreted,  with  eight 
rounded  detached  whorls,  connected  only  by 
elevated  acute  oblique  ribs  ;  the  aperture  round, 
outer  line  thickened,  and  reflected ;  the  colour 
snow-white,  sometimes  pale  flesh  colour  :  the  size 
varies  from  an  inch  and  half  to  two  inches  in 
length.  The  aperture  is  closed  by  a  horny  spiral 

This  elegant  shell  when  perfect  is  valued  at 
a  high  price,  on  account  of  its  rarity.  The 
numerous  ribs  mark  the  different  periods  of  its 
increase,  and  are  in  fact  the  reflected  margins 
of  its  former  apertures,  produced  at  its  various 
stages  of  growth.  It  is  found  in  the  warm  seas 
of  the  east.  There  is  a  shell  which  inhabits  the 
European  and  American  Seas,  and  is  found  upon 

*  From  annulus,  the  Latin  word  for  a  ring, 
t  Plate  IV.  figure  7. 

J  A  corruption  of  the  German  windel-treppe,  a  winding 


our  coasts,  though  not  abundantly.,  called  Turbo 
Clathrus,  or  False  Wentle-trap.*  It  differs  from 
the  true  Wentle-trap  principally,  in  having  its 
whorls  contiguous.  The  inhabitant  is  one  of  the 
animals  that  yield  a  purple  dye  :  if  kept  some 
days  out  of  water  it  becomes  sickly,  and  dis- 
charges a  most  beautiful  purple  liquid.  This 
dye  differs  in  many  respects  from  that  obtained 
from  the  Buccinum  Lapillus.  It  can  be  pro- 
duced spontaneously  from  the  mollusks ;  the 
colour  when  first  it  comes  from  this  animal  is 
purple,  and  not  of  the  same  unalterable  nature 
as  that  obtained  from  the  other.  These  shells 
now  form  a  separate  genus  called  Scalaria. 

Genus    HELIX  f— Plural,  Helms. 


Generic  Character.  Shell  univalve,  spirally 
convoluted,  sub-diaphanous,f  thin  and  fragile  ; 
aperture  entire,  contracted,  sub-orbicular;  body 
whorl  projects  into  the  mouth,  separating  the 

*  Plate  IV.  figure  8.  t  Plate  V.  figure  1,  2,  3. 

£  Diaphanous  is  from  the  Greek  words  5ta,  (dia)  through 
and  Qaivw,  (phaino)  I  appear. 

HELIX—  SNAIL.  107 


The  shape  of  the  Helix  varies  considerably  : 
some  of  the  species  exhibit  quite  a  turreted 
form ;  *  in  others  the  whorls  are  arranged  on  a 
horizontal  plane,f  so  that  the  spire  is  quite  flat- 
tened, and  the  course  of  the  volutions  may  be 
seen  either  from  the  upper  or  under  part  of  the 
shell.  Many  display  a  form  between  these  two 
extremes;  others  again  are  turbinate,  and  of  a 
globose  appearance.  J 

There  is  not,  perhaps,  any  thing  in  animated 
nature  more  abundant  or  universally  diffused 
than  snails ;  the  butterfly  alone  can  compete  with 
them  in  this  respect.  Snails  are  found  in  the 
most  barren  and  desert  wastes.  There  are  parts 
of  the  great  Sahara  destitute  of  all  manner  of 
herbage,  except  here  and  there  a  tuft  of  coarse 
grass,  or  a  solitary  stunted  laurel,  which  accord- 
ing to  the  Psalmist's  description,  "  withereth 
before  it  be  plucked  up."  Yet  these  parched 
specimens  of  vegetation  are  sometimes  quite 
studded  with  snails.  It  has  often  been  conjec- 
tured, that  snails  were  in  part  the  food  of  the 
Israelites,  when  they  took  their  rapid  flight  from 
Egypt;  for  the  country,  through  which  they 
passed  in  their  way  to  the  Red  Sea,  is  described 

*  Plate  V.  figure  3.  t  Plate  V.  figure  2. 

J  Plate  V.  figure  1. 


by  one  who  traversed  it,  as  having  a  herbage 
underneath  the  trees  and  shrubs,  which  is  com- 
pletely covered  with  snails  of  a  prodigious  size, 
and  of  the  best  sort ;  and  in  that  country  these 
animals  are  esteemed  a  delicacy. 

Snails  furnish  a  valuable  article  of  food  on 
the  shores  of  the  Mediterranean,  where  they  are 
boiled  in  their  shells,  and  served  up  with  rice. 
They  possess  nearly  the  same  nutritious  qua- 
lities as  oysters,  and  the  use  of  them  has  often 
proved  efficacious  in  consumptive  disorders. 

The  Helices  which  live  on  land  become  torpid 
on  the  approach  of  winter,  and  generally  cover 
the  mouth  of  their  shell  with  an  operculum. 
Like  that  of  other  terrestrial  mollusca,  this 
covering  is  not  attached  to  the  animal,  but  to  the 
shell,  and  is  deciduous,  acting  only  as  a  preserva- 
tive against  the  cold  of  winter. 

The  history  of  this  genus  is  very  interesting 
and  instructive,  affording  a  striking  instance  of 
the  superintending  providence  of  the  Almighty, 
and  his  care  for  the  peculiar  wants  of  His  crea- 
tures ;  though  all  things  are  at  his  command, 
He  is  not  prodigal  of  means  ;  He  gives  what  is 
required,  and  holds  back  what  is  needless.  Upon 
the  animals  who  inhabit  the  rocky  shores,  or 
bottom  of  the  ocean,  He  has  bestowed  a  thick 
substantial  covering;  but  to  snails,  the  greater 
number  of  which  live  on  the  land,  or  in  stag- 
nant pools,  or  peaceful  streams,  He  has  given  a 
thin  and  remarkably  light  shell,  which,  while  it 
affords  ample  protection  to  its  inmate,  offers  no 


impediment  to  its  loco-motive  propensities.  Can 
we  see  this  beautiful  adaptation  to  circum- 
stances— this  provision  for  the  wants,  and  consi- 
deration for  the  comforts  of  His  creatures,  and 
not  give  the  praise  and  adoration  to  Him,  who 
riding  upon  the  wings  of  the  winds,  regards  not 
only  the  sons  of  men,  but  the  meanest  reptile 
that  crawls  upon  the  earth  ! 

HELIX  Pomatia* 


Specific  Character.  Shell  nearly  globular, 
turbinate,  with  five  rounded  whorls  strongly 
wrinkled  longitudinally  ;  aperture  semi-lunar, 
margin  rather  thickened,  and  turned  a  little 
outwards ;  the  columellar  lip  much  reflected 
over  the  umbilicus  ;  colour  dingy  yellowish 
brown,  commonly  with  three  faint  bands  on  the 
body  whorl ;  one  of  which  continues,  round  the 
next  whorl ;  size  about  two  or  three  inches  in 
length,  and  nearly  equal  in  breadth, 

This  is  the  largest  species  of  land  shell  found 
in  England.  It  is  not  a  native  of  this  country, 
but  was  originally  introduced  about  the  middle 
of  the  sixteenth  century,  either  as  an  article  of 
food,  or  for  medicinal  purposes.  It  is  supposed 
to  have  been  first  imported  from  Italy  into 
Surrey,  by  a  Mr.  Howard  of  Albury ;  the  animals 
increased  there  prodigiously,  and  are  now  become 

*  Plate  V.  figure  1. 


the  most  common  species  about  Box  Hill, 
Ashtead,  and  that  neighbourhood.  They  were 
introduced  into  Buckinghamshire  as  a  medicine 
for  a  lady  who  was  in  a  consumption.  They  are 
commonly  used  as  food  by  the  Roman  Catholics 
in  many  parts  of  Europe  during  Lent,  and  are 
preserved  and  fattened  for  that  purpose  in  large 
reservoirs,  the  floors  of  which  are  covered  with 
herbs  and  flowers.  These  mollusks  were  among 
the  dainties  of  the  luxurious  Romans,  who  had 
their  Cochlearia  or  nurseries  for  snails,  where  the 
animals  were  fed  on  bran  and  wine,  till  they  in- 
creased to  such  a  size,  that  if  we  may  credit 
Varro,  a  shell  has  been  known  sufficiently  large 
to  contain  ten  quarts  of  liquid.  It  is  mentioned  as 
a  remarkable  fact  relating  to  this  shell,  that 
when  the  animal  is  in  a  diseased  state,  the  spire 
becomes  much  elongated. 

HELIX  Hortensis. 


Specific  Character.  Shell  subglobular,  smooth, 
diaphanous  with  fine  transversely  banded  whorls; 
aperture  roundish,  semiorbicular,  the  outer  lip 
slightly  reflected ;  the  colour  of  the  shell  and 
the  bands  are  exceedingly  various  ;  greatest 
diameter  less  than  an  inch. 

This  is  the  most  common  species  of  snail.  At 
the  approach  of  winter,  it  forms  an  operculum 
of  a  coriaceous  substance,  composed  of  several 


coatings,  and  finding  a  retreat  at  the  roots  of 
trees,  and  under  old  walls,  it  braves  the  rigours 
of  the  season.  Its  circulation  is  most  remark- 
ably sluggish,  and  its  movements  are  correspond- 
ingly slow;  but  the  thick  juices  which  prevent 
its  activity,  enable  it  to  bear  the  severity  of 
winter,  so  that  no  cold,  however  intense,  has 
been  known  to  freeze  it.  Again  these  juices, 
though  they  retard  the  progress  of  the  animal, 
furnish  it  by  means  of  their  viscidity,  with  the 
power  of  travelling  with  its  house  on  its  back 
up  perpendicular  ascents,  or  across  horizontal 
surfaces.  Snails  do  not  usually  crawl  out  in 
search  of  nourishment,  except  in  rainy  seasons, 
or  in  damp  shady  places ;  in  time  of  drought, 
they  take  their  station  under  stones  and  leaves, 
or  in  the  cavities  of  the  trunks  of  trees.  The 
eggs  of  the  snail  are  round  and  white;  and 
covered  with  a  soft  shell,  adhering  to  each  other 
in  clusters ;  the  parent  hides  them  with  great 
care  in  the  earth. 

HELIX  lanthma. 



Specific  Character.  Shell  with  four  whorls 
obliquely  situated,  subglobular,  thin,  fragile, 
diaphanous  :  aperture  subtriangular,1  the  angle 
formed  by  the  upper  and  lower  part  of  the  outer 
lip  rounded  ;  columella  straight,  and  elongated, 
the  inner  lip  turned  back  over  it;  colour  violet, 


palest  towards  the  summit :  size  an  inch  long, 
the  breadth  rather  exceeds  the  length. 

This  shell  beautiful  in  its  form  and  colour,  is 
still  more  interesting  in  its  history,  as  displaying 
another  instance  of  the  overruling  care  of  the 
Creator,  and  of  his  compensatory  providence. 
Unlike  most  fragile  shells,  its  dwelling  is  the 
stormy  ocean ;  but  as  the  feeble  reed  bends  to 
the  mighty  wind,  and  rises  unhurt  when  its 
power  is  suspended,  so  this  delicate  shell  offering 
no  resistance  to  the  sea,  rides  upon  its  waves  in 
perfect  safety  ;  and  as  if  still  more  to  diminish 
its  gravity,  the  shell  has  no  solid  columella. 
It  is  always  found  floating  upon  the  water,  and 
probably  never  visits  the  bottom,  or  willingly 
approaches  any  shore.  It  is  thus  supported  on 
the  surface,  by  means  of  a  small  cluster  of 
bubbles  composed  of  transparent  vesicles  which 
it  can  inflate  with  air  at  pleasure,  and  thus  buoy 
up  its  delicate  bark.  Every  shell  contains 
about  a  teaspoonful  of  liquor  of  a  most  beautiful 
red  purple,  which  is  easily  discharged,  as  soon 
as  the  animal  is  touched.  It  is  said  also  to  shine 
by  night  with  a  phosphorescent  light.  This  shell 
had  always  been  considered  a  Helix  by  Linneus 
and  others,  until  the  time  of  Lamarck  who 
determined  it  to  be  necessary  to  place  it  in  a 
distinct  genus.  He  ascertained  that  its  inha- 
bitant differed  essentially  from  the  snail.  The 
organ  which  in  the  snail  is  considered  a  foot, 
was  found  not  to  be  fit  for  crawling,  but  swim- 
ming, being  covered  with  the  air  bladders 


before  mentioned.  It  inhabits  the  coasts  of 
Europe,  Asia,  and  Africa,  and  is  common  in 
the  Mediterranean.  A  few  specimens  have  been 
picked  up  on  the  Welsh  coasts,  but  these  were 
probably  driven  there  by  storms. 

HELIX  Obscura. 


Specific  Character.  Shell  sub-oval,  rather 
obtuse,  opaque,  with  about  six  longitudinally 
wrinkled  whorls  ;  aperture  roundish,  lunar  ;  it  is 
of  a  brownish  horn  colour,  and  the  outer  lip 
white,  with  a  reflected  margin ;  length  half  an 
inch,  breadth  one  fourth,  or  one  sixth.  These 
shells  are  usually  covered  with  an  epidermis, 
which  varies  according  to  the  situations  they 
occupy  ;  and  the  colour  being  regulated  by  that 
of  the  substance  to  which  they  attach  them- 
selves, they  thus  escape  observation. 

Genus-NERITA.*  Plural,  Nerita. 


Generic  Character.     Shell  univalve,  spirally 
convoluted,  retuse,  gibbous,  flattish  underneath ; 

*  Plate  V.  figures  4,  5. 


aperture  simi-lunar ;  columellar  lip,  truncated, 
flattish,  straight,  and  oblique  to  the  axis  of  the 


There  is  no  genus  more  easily  distinguished 
than  that  of  Nerita.  The  semilunar  aperture 
and  straight  flat  columellar  lip  are  its  decided 
characteristics.  There  are  a  few  species  which 
might  pass  for  Turbines,  the  columellar  lip  not 
preserving  its  straightness  ;  but  even  in  these 
doubtful  shells  it  is  flat,  and  therefore  their 
proper  place  in  this  genus  is  obvious.  Some  of 
the  species  have  an  umbilicus  ;  and  in  some  the 
columellar  lip  is  beset  with  strong  teeth.  The 
Nerites  are  all  either  fluviatile  or  marine,  the 
former  are  thin  and  generally  have  a  bright  polish 
on  their  surface  ;  nothing  can  exceed  the  beauty 
and  delicacy  of  the  minature  painting  with  which 
many  of  them  are  adorned.  When  viewed 
through  a  microscope  the  most  highly  finished 
touches  are  discernible.  They  are  worn  as 
ornaments  by  the  Indians.  They  are  now 
formed  into  a  new  genus  called  Neritina.  The 
marine  species  are  distinguished  by  their  solid 
substantial  shells,  often  having  elevated  rounded 
ribs.  The  animal  has  a  short  foot,  and  two 
setaceous  tentacula,  having  eyes  at  their  base. 


NERITA  Peloronta* 


Specific  Character.  Shell  solid,  thick,  semi- 
globular,  turbiuate,  imperforate,  slightly  ribbed 
transversely  ;  spire  flat ;  aperture  entire,  semi- 
lunar  ;  outer  lip  crenulate,  inner  lip  rather  con- 
cave, with  two  or  three  large  teeth  and  an  irre- 
gular saffron  or  blood-coloured  spot  in  the 
middle  ;  ground  of  the  shell  whitish  or  pale  grey 
with  irregular  black  and  red  or  purplish  longi- 
tudinal zig-zag  markings  :  aperture  white,  and 
throat  pale  saffron-colour. 

The  shells  of  this  species  inhabit  the  ocean 
and  are  found  in  the  West  Indies,  Red  Sea,  and 
Mollucca  Islands.  The  animal  is  furnished 
with  an  operculum  which  opens  and  shuts  at  its 
pleasure,  like  a  door  upon  its  hinges,  having  a 
little  prominence  within  the  shell  at  the  lower 
end  of  the  lip,  between  which  and  the  inner  lip 
a  small  projection  of  the  operculum  slides  as  it 

NERITA  Corona. 

Specific  Character.  Shell  globose,  striated ; 
spire  short  eroded ;  f  body  whorl  large  with  a 

*  Plate  V.  figure  4. 

t  Eroded,  gnawed  out  from  Latin  e,  out,  and  rod  ere,  to 

I  2 


transverse  row  of  long  spines  ;  generally  coated 
with  a  black  epidermis ;  length  from  half  to 
three  quarters  of  an  inch,  about  two  thirds  as 

This  shell  has  an  operculum,  which  is  testa- 
ceous, covered  with  a  horny  epidermis  of  a 
semicircular  form,  exactly  closing  the  aperture, 
and  furnished  internally  with  a  dentiform  appen- 
dage, which,  when  the  aperture  is  closed,  lies 
between  a  prominence  at  the  lower  part  of  the 
aperture,  and  the  end  of  the  inner  lip. 

The  columella,  together  with  the  inner  part 
of  the  spire,  and  even  a  part  of  the  lip  is  absor- 
bed by  the  animal,  in  proportion  as  it  increases 
in  size,  whence  it  appears  to  have  no  colu- 

NERITA   Littoralis. 


Specific  Character.  Shell  thick,  smooth, 
summit  rather  obtuse ;  whorls  four  or  five,  body 
whorl  large,  the  others  small  and  lateral ;  aper- 
ture lunar,  rather  inclining  to  oval ;  columellar 
lip  not  so  flat  as  usual  in  this  genus ;  colour 
various,  commonly  plain  light  or  orange  yellow, 
red  or  brown,  sometimes  prettily  mottled,  or 
marked  with  one  or  two  paler  transverse  bands  ; 
size  about  three-fourths  of  an  inch  long,  breadth 
rather  exceeding  the  length. 

This  species  is  extremely  common  on  all  our 


shores,  varying  considerably  in  colour  and 
shape  :  its  roundish  mouth  and  accidental  resem- 
blance of  colour  have  occasioned  some  speci- 
mens to  be  described  as  Turbines* 

Genus— -HALIOTIS.*    Plural  Haliotides. 


Generic  Character.  Shell  univalve,  ear- 
shaped,  open  ;  spire  flat,  lateral,  retuse,  nearly 
concealed ;  aperture  almost  as  large  as  the  shell ; 
the  disk,  f  excepting  in  one  or  two  species,  has 
a  series  of  perforations  parallel  to  the  collumellar 


The  ear-like  shape,  the  flattened  spire  and  the 
row  of  perforations  on  the  disk  readily  distinguish 
this  genus  from  every  other.  The  outside  of  the 
shell  is  generally  rough,  worn  or  covered  with 
marine  substances.  The  inside  is  enamelled  with 
mother-of-pearl,  exhibiting  a  beautiful  iridescent 
play  of  colours.  Each  period  of  the  shell's 
increase  is  marked  by  a  new  hole,  and  till  the 

*  Plate  V,  figure  2. 

•j*  Disk,  a  rounded  surface,  from  the  Latin,  discus,  a  dish 
or  platter. 


final  addition  is  made,  there  is  a  notch  in  the  last 
perforation  m  which  the  animal  places  its  siphon. 
When  a  new  hole  is  opened,  one  toward  the  spire 
is  closed,  and  there  are  seldom  more  than  seven  or 
eight  unstopped  at  the  same  time.  When  the 
Haliotides  traverse  the  rocks,  their  shell  is  like  a 
reversed  basin,  and  the  circumference  is  bordered 
by  the  foot  of  the  animal,  which  is  very  large  ; 
the  spire  is  at  the  posterior  part  as  it  advances. 
In  their  repose  they  adhere  to  the  rocks  with 
such  tenacity  that  it  requires  the  utmost  force 
to  disengage  them,  though  they  can  with  the 
greatest  facility  remove  themselves.  They  are 
always  found  near  the  surface  of  the  water,  and 
in  serene  summer  nights  they  feed  on  the  vegeta- 
tion which  springs  up  on  the  shore.  All  the 
shells  of  this  genus  are  marine,  as  the  name  im- 
plies, being  derived  from  «X$  (hals)  sea,  and  UTO, 
(ota)  ears.  Most  of  the  species  inhabit  the  seas 
of  warm  climates.  They  have  no  operculum. 

HALIOTIS  Tuberculata* 


Specific  Character.  Shell  strong,  thick,  sub- 
ovate,  transversely  wrinkled,  striated  longitudi- 
nally, and  tuberculated  ;  near  the  inner  margin 
is  a  ridge  extending  the  length  of  the  shell,  and 

*  Plate  IV.  figure  2. 


terminating  in  one  spiral  turn  at  the  end,  a  little 
produced  ;  this  ridge  is  beset  with  tubercles 
which  increase  in  size  as  they  recede  from  the 
apex ;  the  last  six  are  open  ;  when  cleared  of 
extraneous  matter  with  which  it  is  constantly 
covered,  the  outside  is  of  a  reddish  brown  colour 
frequently  mottled ;  the  inside  is  a  beautiful 
mother  of  pearl.  The  outer  lip  forms  a  flat  ridge 
quite  up  to  the  spire,  and  is  pearly  like  the 
inside ;  the  length  is  from  three  to  four  inches, 
the  breadth  between  two  and  three. 

These  shells  inhabit  the  deep ;  and  they  are 
sometimes  thrown  upon  our  southern  coasts  after 
violent  storms.  In  Guernsey  they  are  found  in 
great  plenty  adhering  to  the  rocks  at  the  lowest 
ebb  tide.  The  animal  is  eaten,  and  forms  a  very 
savoury  dish ;  the  shells  are  used  to  adorn  the 
houses  of  the  common  people,  in  the  plaster  on 
the  outside  of  which  they  are  studded,  and  their 
pearly  iridescence  glitters  beautifully  in  the 


Genus— PATELLA.*— Plural,  Patella. 


Generic  Character.  Shell  univalve,  without  a 
regular  spire,  dilated,  conical,  entire,  concave 
beneath  in  proportion  as  it  is  convex  above. 


The  shells  of  this  genus  are  easily  distinguished 
from  all  others  by  their  conical  form  and  dilated 
aperture ;  but  they  are  subject  to  many  pecu- 
liarities, and  are  therefore  divided  into  several 
natural  groups.  Some  are  remarkable  for  an 
internal  chamber  or  partition,  which  however 
varies  greatly  in  its  appearance.  In  the  Patellae, 
called  the  Slippers,  it  is  formed  by  the  columel- 
lar  lip,  which  is  straight  and  produced  into  a 
flat  horizontal  plate  extending  half  over  the 
mouth  of  the  shell ;  these  now  form  a  genus 
called  Crepidula.  In  others,  this  appendage  re- 
sembles a  cup  and  is  situated  at  the  apex  within 
the  shell,  which  is  commonly  called  from  its  shape 
the  Cup  and  Saucer  Limpet ;  f  it  is  now  sepa- 
rated from  the  Patellae  and  forms  the  genus 
Calyptraea.  The  apex  of  many  of  the  Patellae 
is  perforated,!  and  this  peculiarity  in  the  shell 

*  Plate  V.  figure  7,  8,  and  Plate  VI.  figure  1. 
f  Plate  V.  figure  7.  J  Plate  V.  figure  8. 


is  connected  with  a  different  formation  of  the 
animal,  whose  gills  are  situated  near  the  hole 
through  which  it  receives  the  needful  supply  of 
water;  these  now  belong  to  the  modern  genus 
Fissurella  ;  others  which  have  a  fissure  or  notch 
at  the  margin  are  called  Emarginula.  In  some, 
the  apex  is  very  retuse  ;  whilst  in  others  it  is 
pointed  and  elegantly  recurved.* 

This  genus  is  peculiarly  interesting  to  those 
who  love  to  trace  the  regular,  but  almost  im- 
perceptible gradations  existing  in  the  scale  of 
nature.  The  species  with  the  recurved  apex 
seem  to  form  the  link  which  connects  the  Patellae 
with  spiral  shells,  whilst  the  other  species,  where 
there  is  no  trace  of  any  volutions,  present  the 
intermediate  grade  between  them  and  the  shells 
entirely  destitute  of  spires. 

The  animal  of  the  Patella  has  a  large  fleshy 
proboscis,  and  two  tentacula,  with  the  eyes  on  a 
small  elevation  at  their  base  ;  the  mouth  has 
cartilaginous  plates  for  the  mastication  of  its 
food.  It  has  a  ventral  foot,  fleshy,  and  fur- 
nished with  numerous  muscular  filaments,  which 
uniting  on  the  upper  part  of  the  mantle,  form 
a  strong  muscle  by  which  the  body  adheres  to 
the  shell.  By  the  action  of  this  muscle,  the  shell 
can  be  brought  close  to  the  surface  to  which  the 
foot  adheres,  or  removed  to  a  distance :  and  it 
is  by  means  of  this  instrument,  that  the  animal, 
when  desirous  of  changing  its  situation,  is  able 

*  Plate  VI.  figure  1. 


to  effect  a  considerable  leap.  Its  locomotive 
powers,  however,  are  but  little  exercised  :  it 
appears  to  live  habitually  in  the  same  spot,  and 
rarely  to  perform  any  other  movement  than  that 
of  slightly  elevating  the  shell,  that  the  water  it 
breathes  may  reach  the  respiratory  organs. 
These  shells  are  generally  found  attached  to 
rocks,  sea- weed,  and  other  marine  substances  ; 
and  in  such  numerous  clusters  that  the  stones 
appear  quite  studded  with  them;  they,  adhere 
with  considerable  tenacity,  and  are  not  easily 
displaced.  They  fix  themselves  thus  securely, 
by  first  applying  their  fleshy  foot  and  the  edge 
of  their  mantle  to  the  substance  on  which  they 
take  up  their  abode  ;  and  then  they  form  an 
internal  vacuum  by  the  contraction  of  their 
muscles,  and  the  pressure  of  the  external  air 
keeps  them  firmly  fixed  to  the  spot.  Thus  ad- 
hering to  a  solid  basis,  and  presenting  a  shell 
whose  conical  form  is  well  calculated  to  break 
the  force  of  the  rough  winds  and  dashing  waves, 
this  little  animal  in  its  exposed  situation,  exhibits 
a  striking  instance  of  the  wise  provision  of  the 
Almighty  for  the  protection  of  his  creatures. 
This  genus  is  found  is  all  parts  of  the  world,  but 
abounds  particularly  in  the  Island  of  Cyprus. 
Its  name  signifies  a  little  dish,  an  appellation 
suggested  by  its  form.  The  animal  feeds  on 
sea-weed  and  marine  vegetables.  The  manner 
in  which  the  Limpet  attaches  itself  to  the  rocks 
and  thus  seeks  shelter,  is  beautifully  described 
and  applied  in  the  following  verses ; 


6  In  Nature's  all-instructive  book, 

Where  can  the  eye  of  reason  look, 

And  not  some  gainful  lesson  find 

To  guide,  and  fortify  the  mind ! 

The  simple  shell  on  yonder  rock 

May  seem,  perchance,  this  book  to  mock — 

Approach  it  then,  and  learn  its  ways, 

And  learn  the  lesson  it  conveys. 

At  distance  viewed,  it  seems  to  lie 

On  its  rough  bed  so  carelessly, 

That  'twould  an  infant's  hand  obey 

Stretch 'd  forth  to  seize  it  in  its  play  ; 

But  let  that  infant's  hand  draw  near, 

It  shrinks  with  quick,  instinctive  fear, 

And  clings  as  close  as  though  the  stone 

It  rests  upon,  and  it,  were  one  ; 

And  should  the  strongest  arm  endeavour 

The  Limpet  from  its  rock  to  sever, 

'Tis  seen  its  loved  support  to  clasp 

With  such  tenacity  of  grasp, 

We  wonder  that  such  strength  should  dwell 

In  such  a  small  and  simple  shell ! 

And  is  not  this  a  lesson  worth 

The  study  of  the  sons  of  earth  ? 

Who  need  a  rock  so  much  as  we  ? 

Ah !  who  to  such  a  rock  can  flee  ? 

A  rock  to  strengthen,  comfort,  aid, 

To  guard,  to  shelter,  and  to  shade ; 

A  rock,  whence  fruits  celestial  grow 

And  whence  refreshing  waters  flow — 

No  rock  is  like  this  rock  of  ours ! 

Oh  then  if  you  have  learnt  your  pow'rs 

By  a  just  rule  to  estimate  ; 

If  justly  you  can  calculate, 

How  great  your  need,  your  strength  how  frail, 

How  prone  your  best  resolves  to  fail, 

When  humble  caution  bids  you  fear 

A  moment  of  temptation  near, 

Let  wakeful  memory  recur 

To  this  your  simple  monitor, 

And  wisely  shun  the  trial's  shock 

By  clinging  closely  to  your  rock.' 


PATELLA  Grceca. 


Specific  Character.  Shell  ovate,  thick,  opaque, 
strongly  reticulated,*  some  of  the  longitudinal 
ridges  much  coarser  than  the  rest,  and  frequently 
tuberculated  by  the  crossing  of  the  transverse 
striae  ;  apex  lateral,  not  much  elevated,  trun- 
cated and  furnished  with  an  oblong  perforation  ; 
colour  pale,  dull  brown,  or  yellowish  white  ; 
inside  smooth,  white,  sometimes  rayed  with  dull 
red  or  brown  ;  margin  crenated,  sometimes  in- 
dented ;  length  about  three  quarters  of  an  inch, 
breadth  scarcely  half  an  inch,  height  a  quarter. 
It  is  rarely  found  on  the  British  coasts  of  a 
superior  size  ;  some  of  the  foreign  specimens 
are  an  inch  long.  This  shell  belongs  to  the 
modern  genus  Fissurella. 

PATELLA  Pellucida. 


Specific  Character.  Shell  sub-conical,  thin, 
pellucid,  smooth;  summit  slightly  recurved, 
lateral  ;  of  a  dusky  brown  colour,  rayed  with 
dotted  lines  of  the  brightest  azure  blue,  lines 
varying  in  number  from  three  to  seven  ;  length 
nearly  an  inch,  breadth  not  quite  three-quarters. 

This  species  is  common  in  many  parts  of  the 

*  Reticulated,  crossed  like  net  work,  from  the  Latin, 
reticul  um9  a  small  net. 


Cornish  and  Devonshire  coasts ;  it  is  never  found 
adhering  to  rocks,  but  is  picked  up  after 
storms,  having  been  thrown  on  shore  by  the 
agitation  of  the  waves,  along  with  the  sea-weed 
to  which  it  is  attached.  It  is  found  in  abund- 
ance at  Sandwich,  and  always  on  the  same 
plant,  the  stalk  of  which  the  animal  excavates, 
probably  for  food,  and  forms  a  cell,  in  which 
are  sometimes  discovered  two  or  three  of  the 
same  species  together. 

PATELLA  Ungarica* 


Specific  Character.  Shell  conical,  thin,  semi- 
transparent,  finely  striated  longitudinally,  and 
wrinkled  transversely ;  summit  much  recurved, 
and  ending  in  two  or  three  spiral  turns ;  it  is 
usually  covered  with  a  rough  epidermis  which 
projects  beyond  the  margin  and  forms  a  ciliatedf 
border:  beneath,  the  colour  is  reddish,  the  inside 
glassy  white,  or  flesh  colour  ;  the  base,  which  is 
nearly  circular,  varies  from  one  to  two  inches  in 
diameter ;  the  shell  is  rather  more  than  half  as 

This  species,  so  remarkable  for  its  elegant 
form,  is  found  on  the  western  shores  of  Britain, 
but  is  not  common.  It  belongs  to  the  new 
genus  Pileopsis. 

*  Plate  VI.  figure  1. 

f  Ciliated,  bordered  with  a  fringe  like  eye-lashes,  from  the 
Latin  cilia,  an  eye-lash. 


Genus— DENTALIUM.*— PZamZ,  Dentalia. 


Generic  Character.  Shell  univalve,  gradually 
tapering,  straight  or  slightly  curved,  resembling 
a  tooth  without  any  internal  partition,  open  at 
both  ends. 


The  shells  of  this  genus  are  easily  known  by 
their  very  simple  construction ;  they  all  more  or 
less  resemble  a  miniature  tusk,  and  the  name 
derived  from  the  Latin  dens,  a  tooth,  refers 
to  this  form.  There  are  but  few  species,  and 
these  vary  principally  in  external  appearance,  in 
magnitude,  in  the  degree  of  curvature,  and  in  the 
ribs  or  grooves  with  which  some  of  them  are  orna- 
mented. One  of  the  largest,  called,  Dentalium 
Elephantinum  is  often  three  or  four  inches  long, 
and  is  strongly  marked  with  longitudinal  ele- 
vated ribs.  One  species  is  so  minute  that  it  is 
scarcely  discernible  by  the  naked  eye,  and  resem- 
bles a  small  bristle. 

There  is  but  little  known  of  the  inhabitant  of 

*  Plate  VI.  figure  6. 


tbe  Dentalium  ;  some  naturalists  have  supposed 
it  to  be  free,  and  independent  of  its  shell,  but 
later  observations  have  led  to  the  discovery  of 
the  muscle  by  which  it  is  attached  to  its  abode, 
into  which  it  has  been  observed  to  shrink  deeply 
for  protection  from  approaching  danger. 

These  shells  are  found  principally  on  sandy 
shores,  sunk  more  or  less  deeply  in  the  ground, 
and  placed  in  a  vertical  position. 

DENTALIUM  Entalis. 


Specific-  Character.  Shell  slightly  curved, 
slender,  tapering,  smooth,  glossy,  sometimes 
marked  with  a  few  circular  wrinkles  or  annu- 
lations,  colour  white  or  yellowish,  length  an 
inch  and  a  half ;  diameter  at  the  larger  end  two 
tenths  of  an  inch,  and  one  fourth  as  much  at 
the  smaller  end. 

It  is  commonly  found  on  our  coasts,  particu- 
larly those  of  the  west  of  England.  The  animal 
is  very  muscular,  its  shape  is  like  its  conical 
shell,  it  has  a  mantle  with  a  fleshy  collar 
through  which  it  can  protrude  its  head  and  foot. 
Tne  head  is  furnished  with  jaws,  and  lips  bearing 


Genus.— SERPULA.*— PZwraZ,  Serpulas. 


Generic  Character.  Shell  univalve,  tubular, 
gradually  tapering,  usually  adhering  ;  cavity 
often  interrupted  by  dissepimentsf  at  irregular 


These  shells  are  usually  found  in  very  irre- 
gular and  diversified  groups  adhering  to  various 
marine  substances.  They  are  invariably  tubular, 
and  are  either  straight,  or  twisted ;  sometimes 
they  are  isolated  and  detached,  but  are  more 
frequently  found  in  clusters  consisting  of  hun- 
dreds of  spiral  tubes  curiously  interwoven ;  they 
are  sometimes  curled  into  a  spiral  form,  but, 
differ  materially  from  the  convoluted  shells,  as 
they  never  have  any  regular  number  of  whorls, 
or  any  appearance  indicating  that  this  mollusk 
is  directed  in  forming  these  convolutions,  by  an 
invariable  law.  The  name  is  derived  from  the 
Latin  serpo,  I  creep,  and  well  designates  their 
tortuous  t  vermiform  §  appearance.  There  is  very 

*  Plate  VI.  figure  2,  3. 

•I*  Dissepiments  are  the  partitions  in  multilocular  shells: 
from  the  Latin  sepes,  a  hedge,  and  dis,  a  prefix  signifying 

J  Tortuous,  from  the  Latin  tort  ws  twisted. 
§  Vermiform,  from  vennis,  a  worm,  and  forma,  a  form. 


•  little  known  of  the  animal.  The  Serpulae 
abound  in  almost  all  situations  that  are  at  times 
covered  by  the  sea ;  they  are  found  attached 
to  various  marine  substances,  from  the  firmest 
rock  and  the  sea-weed  that  grows  upon  it,  to 
sea-animals  the  most  rapid  in  their  motions.  In 
situations,  where  they  are  not  subject  to  inter- 
ruptions, they  form  patches  of  great  thickness 
and  extent.  Some  of  the  rocks  in  the  island  of 
Gorre  are  covered  with  a  crust  of  them  several 
inches  thick,  and  more  than  twenty  feet  square. 

SERPULA  Tubylaria. 


Specific  Character.  Shell  taper,  opaque, 
slightly  wrinkled  transversely ;  the  smaller  end 
is  usually  convoluted  irregularly,  flexuous  or 
variously  twisted,  fixed  ;  the  larger  end  fre- 
quently detached  for  half  its  length  ;  diameter 
at  the  larger  end  two-tenths  of  an  inch  ;  length 
four  or  five  inches. 

This  is  by  no  means  a  common  shell ;  it  is 
found  at  Tor  Cross,  Devonshire  ;  the  head  of 
the  animal  inhabiting  it  is  long,  white,  banded 
with  pink  and  green,  and  has  two  beautifully 
feathered  tentacula,  originating  from  a  single 


SERPULA  Aquaria* 


Specific  Character.  Shell  taper,  straight, 
with  a  convex  disk  at  the  summit  perforated  so 
as  to  resemble  the  rose  of  a  watering  pot,  having 
also  a  radiated  border :  the  colour  is  white  with 
a  slight  tinge  of  pale  red  or  grey;  the  shell 
when  perfect  is  nearly  a  foot  long,  and  more  than 
an  inch  in  diameter  at  the  dilated  summit. 

This  most  singular  and  beautiful  shell  is  rare ; 
it  is  found  in  the  East  Indies.  It  bears  a  great 
resemblance  to  the  spout  and  rose  of  a  watering- 
pot.  It  is  now  separated  from  the  Serpulse 
under  the  generic  name  Aspergillum. 

Genus.— TEREDO.  (Plural,  Teredines.} 


Generic  Character.  Shell  tubular,  tapering, 
flexuous,  lodged  in  woody  substances,  with  two 
hemispherical  valves,  covering  the  head  of  the 
animal,  and  two  others  of  a  lanceolate  shape 
near  the  extremity  of  the  tail. 

*  Plate  VI.  figure  3. 



Many  doubts  have  arisen  whether  this  genus 
ought  to  be  retained  among  the  univalve  shells. 
Some  naturalists  consider  the  two  hemispherical 
valves  as  properly  the  shell  of  the  animal  since 
it  adheres  to  them  by  a  strong  muscle,  and  has 
its  head  lodged  in  them,  and  they  regard  the 
tube  with  the  posterior  valves  as  only  accessory. 
The  use  of  the  tube  is  to  secure  to  the  mollusk  a 
lubricated  passage  and  a  protection  against  the 
rough  surfaces  of  the  wood  in  which  it  resides. 
It  is  formed  by  a  calcareous  secretion,  which 
appears  to  have  a  solvent  power  over  the  resin, 
and  even  over  the  fibre  of  the  wood.  Unless 
this  be  the  case  it  is  difficult  to  account  for  the 
fact,  that  these  creatures  pierce  through  the 
stoutest  oak  timber,  as  they  do  not  seem  to 
possess  any  organ  sufficiently  strong  to  effect 
such  perforations  by  a  simple  mechanical  power. 
On  examining  fresh  specimens,  a  soft  pulpy 
mass  of  a  chalky  appearance,  which  hardens 
when  exposed  to  the  air,  has  been  discovered  at 
the  opening  of  the  hemispherical  valves,  and  is 
no  doubt  the  secretion  with  which  they  lengthen 
the  tube.  This  is  open  at  both  ends,  and 
the  animal  does  not  in  any  way  adhere  to 
it ;  the  posterior  end  is  thickened  and  provided 
with  plates  which  contract  the  aperture,  and 
render  it  very  small ;  this  part  is  always  even 
K  2 


with  the  surface  perforated.  Near  the  extre- 
mity of  the  animal's  tail  are  situated  the  two 
lanceolate  valves,  they  seem  to  perform  the 
office  of  flood-gates,  admitting  or  excluding  the 
water  as  necessity  may  require.  Linnaeus  con- 
sidered that  the  valves  placed  at  both  ends, 
were  of  the  nature  of  opercula,  and  that  the  tube 
was  the  shell  of  the  animal,  which  he  conse- 
quently placed  amongst  the  univalves.  The 
name  is  derived  from  the  Greek  rcpeu  (tereo)  I 
bore,  expressive  of  the  manner  in  which  the 
animal  is  supposed  to  effect  a  settlement  in 
different  substances. 

TEREDO  Navalis. 


Specific  Character.  Shell  thin,  brittle,  straight, 
or  flexuous,  tapering  ;  inside  smooth,  pervious  ; 
the  smaller  end  thick  and  strong,  furnished  with 
plates  or  laminae,  which  contract  that  part  con- 
siderably, and  leave  a  very  small  opening  ;  the 
anterior  valves  attached  to  the  head  of  the 
animal  are  of  a  hemispherical  form,  brittle,  thin, 
finely  striated,  and  covered  with  a  light  brown 
epidermis ;  in  each  there  is  a  long  flat  curved 
tooth  projecting  inwards.  The  tube  is  white, 
sometimes  a  foot  long,  seldom  so  long  as  the 
animal ;  the  foreign  specimens  exceed  greatly 
in  size  those  found  in  England. 

This  singular  animal  has  proved  exceedingly 


destructive  to  our  shipping.  It  readily  enters  the 
stoutest  timbers,  and  ascends  the  sides  of  the 
loftiest  ships,  most  insidiously  destroying  them. 
When  the  hulk  of  a  ship  is  any  time  under 
water,  the  Teredines  appropriate  it  to  their  own 
use,  and  soon  commence  the  work  of  destruction, 
They  begin  with  the  softest  part,  and  at  first 
the  apertures  they  make  are  so  small  as  scarcely 
to  be  perceptible.  Their  manner  of  carrying  on 
their  labour  is  remarkable :  they  are  careful 
never  to  intrude  upon  the  habitation  of  a  neigh- 
bour, and  even  where  a  piece  of  wood  has  been 
so  excavated  as  to  resemble  a  honeycomb,  no 
communication  or  passage  has  been  discovered 
between  the  perforations,  though  often  separated 
only  by  the  slightest  lamina  of  wood.  They 
always  bore  in  the  direction  of  the  grain  of  the 
timber  ;  if  they  meet  in  their  course  with  another 
shell  or  knot,  they  make  a  turn  ;  when  the  obsta- 
cle is  small,  they  wind  round  it,  and  then  proceed 
onwards,  but  when  large,  rather  than  continue 
any  distance  across  the  grain,  they  make  a  short 
turn  back  in  the  form  of  a  syphon.  The  attacks 
of  this  insidious  enemy  have  not  been  confined 
to  shipping ;  our  dock  yards  also  bear  sad  testi- 
mony to  their  work  of  devastation.  In  Holland, 
where  the  inroads  of  the  sea,  and  of  the  great 
rivers  by  which  that  country  is  intersected, 
have  been  restrained  with  immense  labour  by 
dykes,  the  Teredines  have  proved  very  destruc- 
tive, piercing  and  even  destroying  the  piles 
which  sustained  them. 


Many  remarks  suggest  themselves  in  reading 
the  history  of  this  animal.  How  insignificant 
often  #re  the  means  employed  to  effect  the  most 
important  ends  ;  how  is  the  industry  of  years 
baffled  by  the  gradual  and  yet  certain  work  of  a 
little  worm.  We  might  at  first  be  at  a  loss  to 
trace  the  wisdom  or  goodness  of  the  Almighty  in 
permitting  the  existence  of  an  animal  fitted 
only  for  what  appears  a  work  of  evil.  A  further 
acquaintance  with  the  subject,  will  however 
bring  us  to  a  very  different  conclusion.  Mon- 
tague, in  speaking  of  them,  says,  "  that  the 
Teredines  and  many  aquatic  animals  were  cre- 
ated by  the  Father  of  the  universe  for  most 
beneficent  purposes,  cannot  be  disputed  ;  for 
though  they  may  seem  to  impede,  and  even  to 
destroy  the  operations  of  man,  yet  they  are  of  such 
importance  in  the  great  scale  of  nature,  that  it  has 
been  observed,  and  it  would  not  be  difficult  to 
prove,  that  we  should  feel  the  loss  of  one  or  two 
species  of  larger  quadrupeds  more  than  one  or 
two  species  of  these  destructive  animals.  The 
immense  trees  and  forests  of  tropical  countries, 
either  overthrown  by  tornadoes,  or  partially 
destroyed  by  insects,  when  carried  by  rapid 
torrents  into  the  rivers,  would  not  only  choke 
them  up,  but  even  endanger  the  navigation  of 
the  neighbouring  seas,  were  it  not  for  these  small 
yet  powerful  agents  of  dissolution.  Nothing 
can  more  plainly  demonstrate  the  power  of  an 
all-wise  ruler  of  the  universe  than  the  work 
assigned  to  these  animals,  whose  business  it  is, 
to  hasten  the  destruction  of  useless  matter." 


Genus.— SABELLA.   (Plural,  Sdbella.) 


Generic  Character.  Shell  tubular,  composed 
of  sandy  or  calcareous  particles,  and  sometimes 
fragments  of  shells  agglutinated  together,  and 
united  to  a  membranaceous  sheath  by  a  cement. 


This  genus  is  now  very  generally  dismissed 
from  the  class  of  Testaceous  Mollusca,  as  the 
tubes  in  which  the  animals  are  enclosed  are  more 
or  less  composed  of  extraneous  matter,  and  not  of 
a  testaceous  secretion  prepared  by  the  animal  from 
its  own  body,  and  forming  a  compact  solid 
substance,  which  is  the  true  character  of  a  shell. 
Its  best  claim  to  retain  its  position,  is,  that  the 
mould  to  which  the  various  particles  are 
attached,  is  really  a  calcareous  and  not  an  ani- 
mal substance.  The  name  of  the  genus  is 
taken  from  the  Latin,  sabulum,  fine  gravel  or 
sand,  of  which  material  their  habitations  most 
usually  consist. 


Genus.— NAUTILUS.*— (Plural,  NavtiK.) 


Generic  Character.  Shell  univalve,  spirally 
convoluted,  smooth,  multilocular ;  f  chambers 
perforated  and  connected  by  a  siphunculus  or 
pipe ;  the  dissepiments  are  convex  inwardly,  the 
chambers  gradually  increase  in  size  from  the 
apex.  The  animal  resides  in  the  last. 


The  Nautili  differ  much  in  size  ;  some  being 
too  minute  to  be  observed  by  the  naked  eye, 
while  others  are  a  foot  in  diameter.  In  some 
the  whorls  are  contiguous ;  in  others  they  are 
detached.  The  tube  which  connects  the  chambers 
is  supposed  to  admit  either  air  or  water  as  the 
animal  requires ;  when  the  shell  is  stationed  at 
the  bottom  of  the  sea  the  siphon  is  filled  with 
aqueous  fluids ;  by  excluding  these  the  gravity 
of  the  shell  is  diminished,  and  it  rises  in  conse- 
quence to  the  surface;  when  on  the  contrary 
the  animal  is  inclined  to  descend,  it  contracts 

*  Plate  VI.  figure  4. 

•f*  Multilocular,    having  many  little   chambers,    from    the 
Latin  words,  multus,  many,  and  loculum,  a  little  chamber. 


itself  within  its  boat,  draws  in  water,  and  imme- 
diately disappears.  Though  capable  of  float- 
ing on  the  surface  of  the  sea,  it  is  often  found 
reversed,  and  like  a  snail  bearing  its  house  upon 
its  back.  The  name  is  derived  from  the  Greek 
word  vavnXos  (nautilos)  a  sailor. 

The  animals  inhabiting  the  shells  of  this  and 
the  following  genus  vary  considerably  from  the 
other  mollusca  ;  they  are  called  Cephalopodes,* 
(footed  at  the  head,)  because  their  heads  are 
surrounded  by  arms  or  tentacula.  Their 
bodies  are  fleshy  like  the  other  mollusca,  and 
the  posterior  portion  is  contained  in  the  mantle 
of  the  animal.  The  mouth  is  vertical  and 
armed  with  two  corneous  mandibles  resembling 
the  beak  of  a  parrot.  They  live  in  the  sea, 
are  carnivorous,  and  feed  on  crabs  and  other 
marine  animals.  The  position  of  their  arms 
enables  them  to  seize  their  prey,  and  bring  it  to 
their  mouth.  The  Cephalopodes  which  form  a 
multilocular  shell,  instead  of  being  enclosed 
within  it,  envelop  it  so  as  only  to  leave  a  small 
portion  visible  :  a  tendinous  thread  which  issues 
from  the  extremity  of  the  body  appears  to  attach 
the  latter  to  the  shell,  it  probably  has  some  con- 
nection with  the  siphunculus. 

As  in  the  genus  Teredo  we  observed  how 
extensive  a  work  of  destruction  is  carried  on  by 
a  little  worm,  here  we  have  to  notice  the  reverse 

Cephalopodes.     Having  feet  on  the  head,  from  the  Greek 
(cephale)  a  head,  and  nodes  (podes)  feet. 


of  that  fact.  A  very  small  species  of  the 
Multilocular  Cephalopodes  called  Miliola  (being 
about  the  size  of  a  grain  of  millet)  exhibits  the 
power  of  reproduction  in  an  equally  astonishing 
degree.  Around  Paris  these  shells  are  found  in 
the  fossil  state  in  such  prodigious  quantities, 
that  small  as  they  are,  they  form  the  principal 
part  of  the  immense  masses  of  stone  which 
constitute  several  of  its  quarries. 

NAUTILUS  Pcmpilius.  * 


Specific  character.  Shell  with  an  involuted 
and  concealed  spire,  smooth;  aperture  cordate  ; 
colour  whitish,  with  waved  streaks  of  reddish  or 
yellowish  brown,  pearly  within. 

This  beautiful  shell  is  often  converted  by  the 
inhabitants  of  the  East  into  a  drinking  cup  ;  on 
the  surface  they  engrave  various  ornaments  and 

NAUTILUS  Spirula. 


Specific  Character.  Shell  thin,  brittle,  trans- 
parent, with  five  cylindrical  detached  whorls 
divided  into  numerous  compartments,  distin- 
guished on  the  outside  by  a  depressed  circular 

*  Plate  VI.  figure  4. 


line  ;  the  last  volution  takes  a  straight  direction, 
and  is  remote  from  the  adjoining  one :  aperture 
orbicular,  pearly  within  ;  chambers  separated 
by  their  pearly  plates,  but  communicating  with 
each  other  by  a  small  siphunculus ;  white  or 
cream  colour. 

This  shell  is  so  exceedingly  brittle  that  per- 
fect specimens  are  very  rare.  The  last  chamber, 
which  the  animal  inhabits,  is  a  straight  cylinder, 
but  it  is  so  fragile  that  it  is  very  seldom  any 
vestige  of  it  is  preserved.  In  the  broken  state 
in  which  these  shells  are  found,  they  resem- 
ble a  ram's  horn,  and  so  they  have  been  descri- 
bed, but  when  complete,  they  have  more  the 
appearance  of  the  crosier.  The  mouth  of  the 
animal  is  surrounded  by  ten  arms,  two  being 
longer  than  the  others.  This  Nautilus  is  found 
in  great  numbers  in  the  West  Indies. 

Genus.— ARGON  AUTA.f  (Plural,  Argonautce.) 


Generic  Character.  Shell  univalve,  involuted, 
the  last  whorl  very  large,  having  a  double  tuber- 
culated  carina,  thin,  transparent,  unilocular ; 
aperture  cordate,  entire,  contracted.  This  shell 

*  Plate  VI.  figure  5. 


has  much  the  appearance  of  being  composed  of 
two  pieces  united  by  the  keel,  and  seems  to  be 
the  link  between  the  univalve  and  bivalve 


The  animal  inhabiting  these  elegant  shells  is 
soft  and  fleshy,  and  has  a  large  portion  of  its 
body  enveloped  in  the  mantle  ;  its  head  is 
furnished  with  two  eyes,  and  round  its  mouth 
are  arranged  like  rays  eight  elongated  and 
pointed  tentacula  or  arms.  Two  of  these  have  a 
thin  membrane  extending  more  than  half  their 
length.  This  singular  appendage  the  animal 
can  expand  or  draw  in  at  pleasure.  The  shell 
is  of  a  thin  paperlike  substance,  resembling  in 
form  a  kind  of  boat.  Few  objects  can  be  con- 
ceived more  interesting  than  this  beautiful  animal 
seated  in  its  pearly  little  vessel :  two  tentacula 
erected  with  their  membrane  unfurled  like 
a  sail,  whilst  the  remaining  six,  suspended  over 
the  sides  of  the  little  bark,  perform  the  office  of 
oars.  When  wafted  by  propitious  gales,  it 
calmly  rides  over  the  waves  :  but  should  a  storm 
threaten,  or  an  enemy  approach,  it  precipitately 
hauls  in  its  tackle,  shrinks  into  its  shell,  and 
drawing  in  water  to  add  to  its  weight,  seeks 
protection  in  the  depths  of  the  sea  :  the  danger 
over,  it  diminishes  the  gravity  of  its  shell  by  eject- 
ing the  water,  and  rises  again  to  the  surface. 


It  has  long  been  a  doubt  whether  this  animal 
is  the  true  inhabitant  of  the  Argonauta,  and  it 
is  supposed  by  many  naturalists  to  be  one  of 
the  eight-armed  Sepia  or  Cuttle-fish,  which, 
like  the  Hermit  Crab,  having  destroyed  the 
original  fabricator  of  the  shell,  takes  possession 
of  the  vacated  tenement. 

How  does  this  little  animal  verify  the  words 
of  the  Psalmist,  "  They  that  go  down  to  the 
sea  in  ships,  that  do  business  in  great  waters, 
they  see  the  works  of  the  Lord,  and  his  wonders 
in  the  deep."  Ps.  cvii.  23,  24. 

The  art  of  navigation,  in  the  imagination  of  the 
poet,  owed  its  origin  to  the  expert  management 
of  these  little  instinctive  sailors,  whilst  their 
shell  it  is  said,  suggested  the  first  idea  of  a  vessel. 
The  name  Argonauta,  is  derived  from  vam^c 
(nautes)  a  sailor,  and  Argo,  the  name  of  the  ship 
in  which  Jason  made  his  memorable  voyage  with 
his  companions  the  Argonauts. 



Specific  Character.  Shell  having  a  narrow 
keel  sharply  toothed  on  both  edges  ;  sides  flat, 
with  undulated  forked  ribs  ;  extremely  thin  and 
brittle;  colour  white,  teeth  of  the  keel  brown 
towards  the  apex.  Inhabits  the  Mediterranean 
sea,  and  Indian  Ocean. 

*  Plate  VI.  fig.  5. 



1.  What  are  the  parts  of  an  univalve  shell  ? 

2.  Give  a  description  of  each  part,  with  the 
derivation  of  the  terms. 

3.  How  is  the  genetic  character  of  univalve 
shells  determined  ? 

4.  How  is  the  specific  character  of  univalve 
shells  determined  ? 

5.  Give  a  list  of  the  genera  of  univalve  shells. 

6.  Name  those  which  have  regnlar  spires. 

7.  Name  those  without  spires. 

8.  Which  genera  seem  to  connect  the  shells 
with  spires,  and  those  without  ? 

9.  What  shells  have  longitudinal  apertures  ? 

10.  Which  shells  are  canaliculated,  and  which 
entire  ? 

11.  Which  of  the  univalve   shells   resemble 
each  other  ?  Describe  their  points  of  resemblance 
and  also  in  what  respect  they  differ. 

12.  In  what  respect  do  the  shells  of  warm 
climates  differ  from  those  of  colder  regions  ? 

13.  What   is    the   generic   character   of  the 
Cone  ?  and  what  its  distinguishing  mark  ? 

14.  What  remarkable  instinct  is  exhibited  by 
the  animal  of  the  Cone  ? 

15.  Where  are  Cones  found  ? 

16.  What  is  the    generic    character   of    the 
Cypraea,  and  what  its  most  distinguishing  mark  ? 

17.  What  is  there  remarkable  in  the  manner 


in  which  the  shell  of  the  Cypraea  is  formed,  and 
increased  in  size  ? 

18.  What    is   the   generic  character   of    the 
Bulla,  and  what  its  distinguishing  mark  ? 

19.  What  remarkable  organ  is  possessed  by 
the  animal  of  the  Bulla  ?  Describe  the  organ  and 
its  use. 

20.  Describe  the  peculiar  habits  of  the  animal 
of  Bulla  Fontinalis. 

21.  Give  the  generic  character  of  the  Voluta, 
and  its  distinguishing  mark. 

22.  Into  what  different  families  is  the  Voluta 
subdivided,  and  how  are  they  distinguished  ? 

23.  What    is    the  generic   character   of    the 
Buccinum,  and  its  distinguishing  marks  ? 

24.  Describe  the  different  groups  into  which 
the  genus  Buccinum  has  been  subdivided. 

25.  What  is  the  origin  of  the  name  Buccinum  ? 

26.  What  use  has  been  made  of  the  Bucci- 
num ? 

27.  Describe  the  habits  of  the  Hermit  Crab. 

28.  What  is  the  generic  character  of  Strom- 
bus,  and  what  its  most  characteristic  mark  ? 

29.  Describe  how  the  shells  called  Alatae,  or 
winged   Strombi,  are  increased  at  the  different 
stages  of  the  animal's  growth. 

30.  What    is   the   generic   character  of    the 
Murex,  and  what  is  its  distinguishing  mark  ? 

31.  Describe  the  different  families  into  which 
the   genus  Murex  is  subdivided,    and   mention 
how  the  forms  of  these  shells  are  connected  with 
the  peculiar  habits  of  their  animals. 

144         .  UNIVALVES. 

32.  Which    are    the   shells  anciently   called 
Purpurae  ? 

33.  Describe  tfie  manner  in  which  the  purple 
dye  was  obtained   and  prepared,    the  different 
uses  to  which  it  was  applied,  and  the  circum- 
stance supposed  to  have  led  to  its  discovery. 

34.  What   is   the  generic   character    of    the 
Trochus,  and  what  its  most  distinguishing  mark  ? 

35.  Describe  a  remarkable  peculiarity  in  one 
species  of  Trochus 

36.  What  is  the  generic  character  of  Turbo, 
and  its  distinguishing  mark  ? 

37.  Which  species  of  Turbo  is  remarkable, 
and  on  what  account  ? 

38.  What  is  the  generic  character  of  Helix, 
and   by   what    mark    is  it  particularly  distin- 
guished ? 

39.  What  variety  of  form  is  displayed  in  the 
Helices  ? 

40.  Detail    the   interesting  facts  connected 
with  the  natural  history  of  the  Helix. 

41.  How  does  the  Helix  lanthina  display  the 
compensatory  providence  of  God  ? 

42.  What   is   the   generic   character   of    the 
Nerita,  and  by  what  mark  is  it  readily  known  ? 

43.  What    is    the  generic   character   of    the 
animal  inhabiting  the  Haliotis  ? 

44.  What   is   known   of    the   habits  of   the 
Haliotis,  and  what  is  its  distinguishing  mark  ? 

45.  What  is   the   generic   character   of    the 
Patella,    and     what     its    most    distinguishing 
mark  ? 


46.  Describe  the  different  groups  into  which 
the  genus  Patella  is  subdivided. 

47.  What  is  there  particularly  interesting  in 
the  natural  history  of  the  Limpet? 

48.  What   lesson  has  the  poet  drawn   from 
their  natural  history  ? 

49.  What    is    the   generic  character   of  the 
Dentalium,  and  what  its  distinguishing  mark  ? 

50.  What   is  the   generic   character   of    the 
Serpula,  and  its  distinguishing  mark  ? 

51.  In    what  situations  are    Serpulx   found, 
and  under  what  circumstances  ? 

52.  What    is    the   generic   character  of  the 
Teredo  ? 

53.  WThat   are  the    reasons   for  and   against 
retaining    the     Teredo   amongst    the    univalve 
shells  ? 

54.  Describe  the  work  of  the  Teredo  Navalis. 

55.  What   is   the   generic   character   of    the 
Sabella  ? 

56.  What  is   the    generic    character  of  the 
Nautilus,  and  its  distinguishing  mark  ? 

57.  What  kind  of  animal  inhabits  the  Nau- 
tilus ? 

58.  What  is  there  remarkable  in  the  natural 
history  of  the  Nautilus  ? 

59.  What  is  the  generic  character  of  the  Ar- 

60.  What  position  does  the  Argonauta  appear 
to  occupy  in  the  chain  of  nature  ? 

61.  Describe  the  habits  of  the  animal  inha- 
biting Argonauta. 



The  shells  belonging  to  this  class  are  com- 
posed of  two  pieces  united  by  an  elastic  horny 
ligament  :f  the  part  where  the  valves  are  joined 
together,  is  called  the  cardo,  J  or  hinge,  and 
corresponds  in  position  with  the  back  of  the 
animal  :  it  is  either  plain  or  furnished  with  teeth. 
The  ligament  serves  not  only  to  connect  the 
valves,  but  also  to  open  them,  and  is  either  ex- 
ternal or  internal ;  the  muscle  or  muscles  by 
which  the  animal  is  attached  to  the  shell  keep 
it  closed  :  when  these  are  relaxed,  the  ligament, 
which  was  either  in  a  state  of  tension  or  com- 
pression according  as  it  was  either  external  or 
internal,  by  its  efforts  to  recover  its  position, 
opens  the  valves.  If  the  two  valves  are  quite 
alike,  the  shell  is  said  to  be  equivalve ;  §  if  they 
differ  in  form  or  size,  it  is  called  inequivalve. 
If  the  sides  of  the  valve  are  symmetrical,  the 
valve  is  said  to  be  equilateral ;  ||  if  they  are  not,  it 
is  said  to  be  inequilateral. 

*  For  the  parts  of  a  bivalve  shell,  see  Plate  I. 

+  Ligament,  a  substance  which  serves  to  bind  things  toge- 
ther, from  the  Latin,  ligare,  to  bind. 

J  Cardo  is  the  Latin  word  for  a  hinge. 

§  Equivalve,  having  equal  valves,  from  Latin,  equ  zts, 
equal,  and  valve. 

||  Equilateral,  having  equal  sides,  from  Latin,  *equ  its 
equal,  and  latera,  sides. 


The  animals  belonging  to  the  bivalve  shells 
are  acephalous  mollusca,  and  have  not  a  distinct 
head  ;  they  have  no  eyes,  and  the  mouth,  which 
is  hidden  under  the  mantle,  is  only  a  simple  open- 
ing for  the  reception  of  food,  without  proboscis, 
jaws,  or  any  hard  parts  fitted  for  mastication. 
This  mouth  is  surrounded  by  four  flattened 
moveable  expansions,  which  partake  of  the  na- 
ture of  tentacula.  The  branchice,*  or  gills,  con- 
sist of  two  leaves  or  expansions  on  each  side  of 
the  mollusk,  and  extend  the  length  of  its  body. 
The  mantle  is  large,  sometimes  it  is  quite  open, 
and  bordered  with  contractile,  irritable  fila- 
ments ;  in  some  instances  it  is  joined  in  front, 
forming  tubular  elongations,  called  siphons, 
which  conduct  the  water  to  the  mouth  and 
branchiae.  The  muscles  are  generally  very 
thick  and  strong,  and  hard  at  the  place  of  attach- 
ment to  the  shell ;  those  which  close  the  valves 
are  called  the  adductor  f  muscles.  Many  spe- 
cies have  not  the  power  of  locomotion,  but  are 
immoveably  cemented  to  rocks  or  stones  :  a  few 
are  attached  by  a  cartilaginous  ligament,  others 
by  a  byssus.  These  mollusca  have  no  ventral 
foot  similar  to  that  possessed  by  some  of  the 
cephalous  mollusca  ;  but  some  have  a  muscular 
substance  usually  tongue-shaped  and  capable  of 
considerable  elongation.  This  organ  enables  them 
to  creep,  or  to  effect  a  kind  of  leap,  by  which  they 

*  Branchiae,  is  derived  from  the  Greek,   jS^ayxm   (bran- 
chia)  the  gills  of  fish. 

f  Adductor,  is  derived  from  adduco,  I  bring  together. 
L  2 


change  the  position  of  their  shells  ;  sometimes 
it  is  transformed  into  a  paw,  and  sometimes 
it  is  employed  to  fix  the  silky  filaments  of  a 
byssus.  These  mollusks  do  not  appear  to  possess 
the  different  organs  of  sense,  but  to  be  reduced 
to  that  of  touch  ;  indeed  their  faculties  are 
altogether  much  less  developed  than  those  of  the 
mollusca  cephale.  None  of  the  bivalves  are 
terrestrial  shells,  some  few  are  fluviatile.  The 
generic  character  of  the  bivalves  is  principally 
derived  from  the  formation  of  the  hinge,  and  the 
general  appearance  of  the  shell. 


The  valves. 

The  cardo  or  hinge,  the  part  where  the  valves 
are  united. 

The  beaks  or  apices,  the  points  of  the  valves 
near  the  hinge. 

The  base,  the  part  of  the  shell  opposite  the 

The  umbones  or  bosses,  the  swelled  parts  near 
the  beaks. 

The  ligament,  the  elastic  horny  substance, 
which  connects  the  two  valves. 

The  margin  of  valves. 

The  area  or  anterior  slope,  the  margin  of  the 
valves  near  the  ligament. 

The  areola  or  posterior  slope,  the  margin  of 
the  valves,  the  other  side  of  the  ligament. 

MYA—  GAPER.  149 

The  cavity. 

The  disk,  the  convex  part  of  the  valves 
between  the  umbones  and  margin. 

The  length,  the  direction  of  the  shell  from  the 
beak  to  the  base. 

The  breadth,  the  direction  at  right  angles  with 
the  length. 

The  auriculce  *  or  ears,  small  appendages 
placed  at  the  sides  of  the  hinge. 

The  circumference. 

The  muscular  impressions,  marks  in  the  inside 
of  the  shell  made  by  the  adhesion  of  the  adductor 

The  right  valve,  the  valve  nearest  to  the  right 
hand,  when  the  shell  is  placed  on  its  base  with 
the  area  opposite  to  the  person  looking  at  it. 

The  left  valve. 

The  teeth,  pointed  protuberances  at  the  hinge. 

The  cardinal  teeth,  the  central  teeth,  or  those 
near  the  centre  of  the  hinge. 

The  lateral  teeth,  the  teeth  near  the  sides. 

Genus.— MY  A.-\-— (Plural,  Myce.) 


Generic  Character.    Shell  bivalve,  equivalve, 

*  Auricula,  a    small  ear;    the  diminutive  of   the   Latin 
auris,  an  ear. 

f  Plate  VII.  fig.  1,  2. 


inequilateral,  mostly  gaping  at  both  ends,  gene- 
rally smooth,  or  only  slightly  striated;  shape 
suboval,  broader  than  it  is  long  ;  hinge  with  a 
strong,  patulous,*  or  spoon-shaped  tooth,  some- 
times inserted  into  the  opposite  valve. 


The  points  of  generic  resemblance  in  the 
Myae  are  wanting  in  many  of  the  species.  The 
coarse  large  tooth  is  the  characteristic  of  the 
hinge,  but  sometimes  it  is  not  more  than  a 
thickened  callosity.f  Some  species  are  alto- 
gether destitute  of  teeth  ;  these  have  a  rounded 
cavity  for  the  reception  of  the  cartilage.  The 
gaping  of  the  valves  is  another  distinguishing  fea- 
ture, but  it  does  not  always  occur.  In  form 
also  the  shells  differ  considerably  ;  some  are 
oblong  and  truncated,  as  if  a  part  of  the  shell 
had  been  cut  off;  others  are  orbicular,  and  many 
are  angular  from  the  addition  of  ears  at  the  hinge. 
The  Myae  are  generally  covered  with  a  thick 
brown  or  green  epidermis  ;  when  this  is  removed, 
the  surface  exhibits  a  beautiful  iridescent 
mother-of-pearl  lustre.  Some  of  the  species 
grow  to  a  great  size;  others  are  remarkable  for 

*  Patulous,  lying  open,  spreading,  from  the  Latin,  pat  ere, 
to  lie  open. 

*h  Callosity,  hardness  of  skin  or  flesh,  from  Latin  call  its, 
which  has  the  same  signification  ;  hence  our  English  word 

MYA— GAPER.  151 

their  thick,  solid,  and  substantial  shells,  and 
have  in  consequence  been  formed  into  a  distinct 
genus,  called  IJnio.  Many  of  the  mollusks 
of  this  genus  burrow  in  the  sand  or  mud,  boring 
a  channel  through  which  they  thrust  a  con- 
tractile trunk  inclosing  two  tubes.  The  Myae 
furnish  food  not  only  for  man,  but  also  for  many 
aquatic  birds. 

MYA  Truncata* 


Specific  Character.  Shell  ovate,  convex, 
truncated  at  the  anterior  end,  where  it  gapes 
considerably,  curved  at  the  areola,  wrinkled 
transversely,  and  covered  with  a  brownish  yellow 
tough  epidermis,  extending  an  inch  or  two 
beyond  the  gaping  end,  like  a  thick  membrane, 
through  which  the  animal  protrudes  its  tube  ; 
hinge  with  a  rounded  tooth  projecting  forwards; 
inside  white  ;  length  from  one  to  two  inches ; 
breadth  from  two  to  three. 

These  shells  inhabit  the  sand  or  gravel  about 
low  water  mark  on  most  of  the  northern  coasts 
of  Europe.  In  Greenland,  their  mollusks  are  the 
food  of  man  and  different  animals.  When  taken 
alive,  the  epidermis  of  the  shell  is  found  joined 
to  the  tube  or  proboscis  of  the  animal,  having 

*  Plate  VII.  fig.  3. 


become  a  thick,  tough,  coriaceous*  skin  for 
its  protection.  The  animal  is  capable  of  ex- 
tending this  tube  to  the  distance  of  nine  or  ten 
inches,  and  of  contracting  it  to  about  three,  but 
cannot  withdraw  it  entirely  into  the  shell. 

MYA  Margaratifera. 


Specific  Character.  Shell  strong,  ponderous, 
thick  ;  shape  ovate,  oblong,  front  compressed, 
margin  a  little  contracted  in  the  middle,  giving 
a  somewhat  curved  outline  to  the  circumference ; 
hinge  consisting  of  a  cardinal  tooth  in  one  valve, 
which  is  thick,  obtusely  conical,  and  locking 
into  a  bifurcated  f  tooth  in  the  other  valve ;  shell 
about  two  inches  long,  and  four  broad ;  covered 
with  a  black  epidermis  decor ticatedj  at  the  urn- 
bones  ;  inside  a  greenish  pearly  hue. 

This  shell  is  one  of  a  very  interesting  group, 
now  formed  into  a  distinct  genus  called 
Unio.  It  inhabits  only  rocky  torrents,  and 
the  precipitous  streams  of  mountainous  dis- 
tricts. Many  are  found  in  the  cataracts  and 

*  Coriaceous,  like  leather,  derived  from  the  Latin  cori  urn, 
skin,  leather. 

•f  Bifurcated,  having  a  fork  of  two  teeth :  from  the  Latin 
bis,  twice ;  and  furca,  a  fork. 

J  Decorticated,  having  the  bark  or  outer  skin  taken  off ; 
from  the  Latin  de,  off :  and  cortex,  the  bark  of  a  tree. 

MYA— GAPER.  153 

rapid  rivers  of  America,  and  by  their  solid 
and  thick  shells  manifest  the  providential  care 
that  fitted  them  for  the  dangerous  spots  they 
occupy.  When  we  look  at  the  ponderous 
Mya  driven  by  the  powerful  torrent,  and  com- 
pare it  with  the  light  and  delicate  lanthina, 
borne  gently  on  the  surface  of  the  waves,  shall 
we  coldly  attribute  such  adaptation  to  circum- 
stances to  the  blind  dealing  of  chance,  and  not 
rather  delight  to  recognise  the  beneficent  wis- 
dom of  our  heavenly  Father,  pervading  all  his 
works,  and  suiting  each  animal  to  the  place  he 
assigns  it? 

The  Mya  Margaratifera  is  found  in  several 
of  our  rivers,  particularly  those  of  Wales  ;  also 
in  Ireland,  where  the  peasantry  use  the  valves 
as  spoons.  This  species  has  long  been  celebra- 
ted for  producing  pearls  of  a  good  colour  and 
sometimes  of  a  considerable  size.  These  orna- 
ments appear  to  be  exclusively  the  production 
of  the  bivalve  testacea,  and  are  found  only  in 
the  shells  which  have  a  coating  of  mother-of- 
pearl  in  the  inside  of  their  valves.  Pearls  are 
said  to  be  produced  by  a  disease  of  the  animal, 
occasioning  a  partial  secretion  of  the  sub- 
stance, which  forms  the  inner  coating  of  the 
shell.  The  British  islands,  especially  Ireland, 
have  been  noted  for  their  pearl  fisheries.  The 
Conway  was  formerly  celebrated  for  this  pro- 
duction :  a  large  one  which  was  taken  in  that 
river,  and  presented  by  Sir  Richard  Wynne  the 
chamberlain,  to  Catherine  the  consort  of  Charles 
II.  is  said  still  to  adorn  the  British  crown. 


Genus.— SOLEN  *— (Plural,  Soltnes.) 


Generic  Character.  Shell  bivalve,  equivalve, 
gaping  at  both  ends  ;  form  oblong,  transversely 
elongated  ;  hinge  has  a  subulate,  reflected  tooth, 
sometimes  double,  not  inserted  into  the  opposite 
valve.  Most  of  the  shells  are  brittle;  some 
have  an  internal  rib  extending  from  the  hinge  to 
the  opposite  margin. 


There  is  in  general  but  little  difficulty  in  de- 
termining the  Solenes  :  they  are  recognized  by 
their  oblong  form,  their  disproportionate  breadth, 
and  their  gaping  at  both  extremities.  A  few 
of  the  species,  however,  are  oval,  and  these 
have  their  hinge  nearly  central. f 

The  history  of  this  genus  affords  various  in- 
stances of  ingenuity  in  the  application  of  very 
simple  means.  The  mollusk  is  furnished  with  a 
long  pliable  cylindrical  leg ;  when  it  wishes  to 
bore  a  hole  for  its  residence,  it  extends  this 
instrument  from  the  inferior  end  of  the  shell, 
using  it  as  a  pointed  shovel  to  excavate  the  sand. 
When  the  tunnel  is  partly  formed,  the  animal 

*  Plate  VII.  fig.  3,  4,  5.  f  Plate  VII.  fig.  5. 


advances  the  leg  a  little  farther,  fixes  it  by  its 
point  as  a  hook  in  the  ground,  and  using  this  as 
a  fulcrum,  descends  in  safety,  continuing  the 
operation  till  the  shell  is  buried  about  two 
inches  under  ground.  When  it  wishes  to  regain 
the  surface,  the  leg  is  rolled  up  into  a  spherical 
form,  and  stretched  very  tight ;  by  means  of 
the  ball  thus  formed,  the  little  creature  is  pre- 
served from  slipping  backward,  while  by  the 
action  of  its  muscular  power,  it  throws  the  shell 
forward.  The  peculiar  habits  of  the  Solen 
render  no  other  than  perpendicular  motion  neces- 
sary to  it,  and  therefore  while  the  form  of  its 
shell,  and  the  powers  with  which  it  is  gifted,  are 
admirably  calculated  for  movement  in  this 
direction,  it  is  unable  to  advance  horizontally. 
It  requires  a  safe  retreat  and  a  supply  of  food ; 
the  former  it  obtains  by  withdrawing  into  its 
recess,  and  the  latter  by  ascending  its  channel 
when  the  tide  comes  in  and  brings  the  little 
marine  insects  which  form  its  food.  The 
retreat  of  the  Solen  is  marked  by  a  small  de- 
pression on  the  sand ;  sometimes  the  shells  are 
dug  out  by  the  fishermen,  but  as  this  is  a  labo- 
rious employment,  they  are  often  entrapped  by 
stratagem.  For  this  purpose,  at  the  reflux  of 
of  the  tide,  when  the  men  can  approach  them,  a 
little  salt  is  placed  round  their  perforations, 
which  melting,  is  mistaken  by  the  animal  for 
the  return  of  the  tide,  and  thus  decoyed,  they 
elevate  themselves  in  the  expectation  of  finding 
their  prey.  So  rapid,  however,  are  their  actions 


that  great  dexterity  is  requisite  to  catch  them, 
before  they  again  sink  into  their  retreat,  and  if 
they  are  successful  in  escaping,  they  are  not 
easily  tempted  again  to  the  surface.  In  many 
places  this  animal  is  valued  as  food.  The  name 
Solen,  is  derived  from  the  Greek  a-uXvjv  (solen) 
a  tube.  The  French,  in  allusion  to  the  shape 
of  the  shells,  call  them  manches  de  couteaux. 

Several  species  of  Solen  are  common  on  the 
coasts  of  Britain. 

SOLEN  Siliqua* 


Specific  Character.  Shell  straight,  subcylin- 
drical,  truncated  at  one  end,  and  slightly  roun- 
ded at  the  other  ;  hinge  lateral,  with  a  single 
tooth  in  one  valve,  and  a  lateral  rib  locking 
between  two  teeth  in  the  other,  which  has  also  a 
rib ;  outside  covered  with  an  olive  brown  skin 
striated  transversely,  each  stria  afterwards  taking 
a  longitudinal  direction  ;  beneath  the  epider- 
mis the  shell  is  greyish  white  with  purplish 
streaks;  length  about  one  inch,  breadth  from 
one  open  end  to  the  other,  seven  or  eight  inches. 

This  shell  is  common  on  most  of  our  sandy 
shores;  it  is  found  buried  a  foot  or  more  in 
depth  near  low  water.  In  the  neighbourhood  of 
Belfast,  specimens  of  this  shell  are  found  more 
than  ten  inches  in  length. 

*  Plate  VII.  fig.  4. 


SOLEN  Radiatus* 


Specific  Character.  Shell  oval,  smooth,  thin, 
brittle,  striated  concentrically ;  when  stripped  of 
its  green  epidermis,  it  appears  both  within  and 
without  of  a  delicate  violet  colour,  with  from 
two  to  four  white  longitudinal  rays,  which 
become  broader  towards  the  margin ;  hinge  with 
two  teeth  in  each  valve,  and  a  strong  white 
depressed  rib  extending  somewhat  obliquely 
from  the  hinge  towards  the  margin ;  shell  about 
an  inch,  or  an  inch  and  quarter  long,  and  from 
three  to  four  inches  broad. 

It  is  found  in  the  Indian  Ocean. 

Genus.— TELLINA.f— (P^mZ,  TdRna.) 

Generic  Character.  Shell  bivalve,  equivalve, 
inequilateral ;  shape  either  ovate  and  thickish, 
ovate  and  compressed,  or  suborbicular ;  the 
area  often  compressed,  having  a  flexuous  plait  or 
fold,  and  its  margin  curved  inwards,  so  that  it 

*  Plate  VII.  fig.  5.  f  Plate  VII.  fig.  6,  7,  8,  9. 


always  narrower  than  the  areola.  The  hinge 
has  either  one  or  two  central  teeth  in  each  valve, 
one  of  them  often  bifid  ;  *  the  lateral  teeth  are 
remote,  and  sometimes  wanting  in  one  valve  ; 
the  beaks  are  short,  and  usually  lean  towards 
the  ligament,  which  is  external. 


This  and  the  following  genus  are  so  very 
similar,  that  it  is  often  difficult  to  discriminate 
between  them.  If  however  a  shell  have  its 
anterior  slope  compressed,  or  any  indication  of 
its  margin  being  curved  inwards,  it  may  be 
known  immediately  as  a  Tellina.  The  Tellinae 
are  very  beautiful,  and  are  particularly  remark- 
able for  the  coloured  radiations  with  which  they 
are  adorned.  They  have  generally  a  fine  polish, 
and  are  sometimes  delicately  marked  with  minute 
striae.  They  are  found  buried  in  the  sand  or 
fine  gravel  of  the  sea  shore;  where  they  are 
commonly  the  prey  of  Buccina,  and  other  car- 
nivorous mollusks,  who  pierce  the  shell,  and 
devour  the  inhabitant.  The  mantle  of  the  ani- 
mal is  formed  in  the  front  into  two  siphons  ;  the 
foot  which  it  thrusts  out  of. its  shell  when  de- 
siring to  change  its  position,  is  generally  flat, 
but  sometimes  it  is  straight  and  lengthened  into 
a  kind  of  leg. 

*  Bifid,  cleft  in  two,  from  the  Latin  bis  twice,  and  fid  z,  I 
have  cleft. 


TELLINA  Lingua  Felis* 


Specific  Character.  Shell  suboval,  thickish, 
somewhat  angular  at  the  anterior  end,  rough, 
covered  with  pointed,  rather  arched  erect  scales, 
disposed  in  a  quincunx  f  order;  colour  white, 
often  with  pale  pink  rays,  and  the  umbones  of  a 
fine  pink  ;  length  about  an  inch  and  quarter, 
breadth  about  an  inch  and  three  quarters. 

It  inhabits  the  Indian  Ocean. 

TELLINA  Radiata. 


Specific  Character.  Shell  ovate  oblong,  re- 
flected at  the  anterior  end,  striated  transversely, 
highly  polished  ;  colour  sometimes  wholly  white, 
more  commonly  white  with  red  rays,  or  yellow 
transverse  bands ;  the  hinge  is  not  central,  it  has 
two  small  teeth  in  one  valve,  and  one  in  the 
other,  and  the  lateral  teeth  are  remote ;  it  is 
about  an  inch,  or  an  inch  and  half  long,  and 
more  than  twice  as  broad. 

*  Plate  VII.  fig.  8. 

f  Quincunx,  disposed  alternately  as  in  rows  or  spots,  the 
spots  of  each  row  being  opposite  the  space  between  two  spots 
of  the  next  row ;  from  Latin,  quinqwe,  five,  and  unx,  ounce, 
because  the  weight  representing  five  ounces  was  stamped 
thus  X 

160  .        BIVALVES. 

The  Tellina  Radiata  is  found  very  abundantly 
in  the  West  Indies ;  it  also  inhabits  the  Euro- 
pean ocean. 

TELLINA  Carnaria* 


Specific  Character.  Shell  suborbicular,  rather 
more  produced  on  one  side  than  the  other,  sub- 
pellucid,  marked  with  delicate  minute  crowded 
striae,  which  at  the  centre  are  oblique,  at  the 
shorter  end  curved  and  flexuous,  at  the  pro- 
duced end  straight,  and  which  meeting  the 
oblique  striae  of  the  centre  form  with  them 
angles ;  the  hinge  which  is  towards  the  poste- 
rior side,  has  two  small  teeth  in  one  valve,  and 
one  in  the  other,  with  strong  laminated  lateral 
teeth  ;  flesh  colour  both  within  and  without, 
length  about  three  quarters  of  an  inch,  breadth 
rather  more. 

*  Carnaria    is    derived  from    the  latin  carne,    flesh,  this 
species  being  so  called  from  their  flesh  colour. 


Genus.— CAHVIUM*— (Plural,  Cardia.) 

Generic  Character.  Shell  bivalve,  equivalve, 
nearly  equilateral ;  shape,  convex,  the  contour  of 
many  of  the  species  when  viewed  with  either  of 
the  slopes  in  front,  exhibits  the  form  of  a  heart ; 
surface  either  ribbed,  striated,  or  furrowed  lon- 
gitudinally ;  margins  toothed,  the  ribs  or  fur- 
rows of  the  two  valves  being  so  arranged  as  to 
alternate  at  the  margins,  and  to  fit  closely  into 
each  other ;  the  hinge  has  four  teeth  in  each 
valve,  the  two  central  are  oblique,  approxima- 
ting, and  articulating  with  the  teeth  of  the  other 
valve,  two  lateral  teeth  remote  ;  the  beaks  are 
turned  inwards  ;  the  unbones  are  turgid ;  the 
ligament  is  external. 


The  Cardium   is  readily   distinguished   from 
the  shells  of  other  genera  by  the  peculiarity  of 
its  teeth  and  its  cordate  form  ;  its  ribs  or  striae 
also  are  invariably  longitudinal.     The  mollusks 
of  this  genus  are  furnished  with  two  short  un- 
equal tubes,    fringed    with   hairs   at   their   ex- 
tremities ;    they   have   a   strong  muscular  foot 
which  enables  them  to  move  with  great  rapidity. 
*  Plate  VIII.  figures  1,  2. 


They  live  buried  under  the  sand,  but  select  a 
spot  within  reach  of  the  waves,  as  they  require 
frequent  supplies  of  water,  and  to  obtain  it,  are 
continually  protruding  their  tubes.  Many  of 
the  species  afford  nutriment  to  the  poorer  classes. 
The  name  is  derived  from  the  Greek  Kafita 
(cardia)  a  heart. 

CARDIUM  Edule* 


Specific  Character.  Shell  convex,  sometimes 
produced  at  the  posterior  end,  with  about 
twenty-six  longitudinal  ribs  and  transverse 
wrinkled  striae,  which  in  old  specimens  appear 
somewhat  imbricated  ;  colour  whitish,  or  pale 
ferruginous ;  about  an  inch  and  a  quarter  long, 
and  an  inch  and  a  half  broad. 

This  species  is  very  common  in  most  of  our 
inlets  and  bays  near  the  mouth  of  rivers,  where 
the  shore  is  sandy.  They  are  found  buried 
three  or  four  inches  under  the  surface.  The 
moliusks  when  boiled,  afford  a  wholesome 

CARDIUM  Tubereulatum.^ 


Specific  Character.  Shell  somewhat  orbicular, 
ponderous,  slightly  truncated  at  the  anterior 

*  Edule,  eatable,  from  the  Latin  ed  ere,  to  eat. 
f  Plate  VIII.  fig.  2. 


side,  with  twenty-one  ribs,  the  anterior  ones 
having  sharp  tubercles,  and  the  posterior  thick 
transverse  scaly  plates  ;  colour,  pale  brown,  with 
darker  transverse  bands  ;  breadth  not  quite 
four  inches,  and  rather  exceeding  the  length. 

This  shell,  and  the  Cardium  Echinatum, 
which  it  greatly  resembles,  are  found  in  abund- 
ance on  the  Paignton  sands  in  Torbay,  where  at 
low  tide  they  may  be  observed  with  their 
fringed  tubes  just  appearing  above  the  surface 
of  the  sea.  The  neighbouring  cottagers  collect 
them  in  baskets,  and  after  cleansing  them  in 
cold  spring  water,  fry  the  mollusks  in  a  batter 
made  of  crumbs  of  bread,  which  make  a  whole- 
some and  savoury  dish  ;  they  call  them  Red 

Genus.— MACTRA.*— (Plural,  Mactrce.) 


Generic  Character.  Shell  bivalve,  equivalve, 
inequilateral,  sometimes  gaping  ;  shape  generally 
nearly  triangular  ;  hinge  with  the  cardinal  tooth 
complicated,!  and  an  adjacent  cavity  filled 

*  Plate  VIII.  figures  3,  4. 

f  Complicated,  folded  together,  from  the  Latin  con,  with, 
together,  and  plica  re,  to  fold. 

M  2 


by  the  ligament  which  is  internal,  the   lateral 
teeth  laminar,  double  in  one  valve,  inserted. 


The  shells  of  this  genus  are  clearly  marked 
by  their  angular  central  tooth,  and  internal 
ligament.  They  vary  little  in  form  or  colour- 
ing, and  do  not  display  much  beauty;  they 
are  usually  semipellucid,  and  of  a  thin  delicate 
appearance;  the  surface  is  seldom  diversified 
by  inequalities.  The  prevailing  colour  is  blueish, 
or  yellowish  white,  sometimes  radiated.  The 
animal  has  not  the  power  of  progressive  motion, 
but  by  the  assistance  of  a  small  compressed 
muscular  foot,  it  is  enabled  to  change  its  posi- 
tion, a  little  :  this  organ  projects  at  one  end  of 
the  shell,  and  at  the  other  are  two  tubes  formed 
by  the  mantle.  The  name  Mactra  is  derived 
from  the  Greek  paKrpa,  (mactra)  a  kneading- 

MACTRA  Stultorum* 

Specific  Character.    Shell  subtriangular,  con- 
vex, thin,  brittle,  semipellucid  ;    colour  white 

*  Plate  VIII.  fig.  4. 


grey,  or  pale  brown,  radiate  more  or  less  from  the 
hinge  with  paler  stripes,  sometimes  of  a  purplish 
hue  about  the  beaks,  and  inside  of  the  valves;  the 
umbones  are  gibbous;  length  an  inch  and  a 
quarter,  the  breadth  one  and  three  quarters. 
Common  on  most  sandy  coasts. 

MACTRA  Compressa  or  Piperata. 


Specific  Character.  Shell  subtriangular, 
roundish,  compressed,  thin,  semipellucid,  finely 
striated  ;  umbones  small,  central ;  hinge  without 
lateral  teeth,  cartilage  cavity  large,  triangular, 
cardinal  teeth  small,  a  single  one  locking  into  a 
bifid  one  in  the  opposite  valve  ;  of  a  yellowish, 
reddish,  or  white  colour  often  stained  with  black 
occasioned  by  the  mud  in  which  it  resides  ; 
about  an  inch  and  quarter  long,  and  an  inch 
and  half  broad. 

This  is  one  of  the  most  beautiful  of  the  Bri- 
tish species  of  Mactra ;  it  is  chiefly  found  at  the 
mouth  of  inlets  or  rivers,  not  remote  from  fresh 
water ;  for  though  it  always  seeks  a  spot  within 
reach  of  the  flux  of  the  tide,  it  delights  in  situa- 
tions over  which  fresh  water  occasionally  flows. 
It  lives  in  the  mud,  buried  about  five  or  six  inches 
deep.  The  animal  has  two  slender  tubes  of  a 
yellowish  colour  placed  near  together  at  the  an~ 
terior  end  of  the  shell :  one  about  three  inches 


long  it  protudes  in  search  of  its  food,  which 
consists  of  insects ;  these  may  be  seen  passing  up 
its  transparent  siphon,  drawn  in  with  the  current 
of  water  it  is  continually  receiving,  and  which 
it  discharges  at  the  shorter  tube,  retaining  only 
the  nutritious  matter  it  contained. 

Genus— DONAX  *— (Plural,  Donaces.} 


Generic  Character.  Shell  bivalve,  equivalve, 
inequilateral ;  the  form  like  a  wedge,  broad, 
thick,  and  obtuse  at  the  anterior  end,  and  gra- 
dually narrowing  and  lessening  at  the  posterior  ; 
the  margin  is  often  crenulate,  and  usually 
gaping ;  the  hinge  has  two  central  teeth  in  each 
valve,  and  one  remote  lateral  one  ;  the  ligament 
is  external. 


The  wedge-like  form  of  the  donaces  easily 
distinguishes  them.  The  derivation  of  the  name 
from  Sovaf ,  (donax)  an  arrow,  may  have  been 

*  Plate  VIII.  figures  5,  6. 


adopted  either  as  indicative  of  the  sagittate 
form,  or  of  the  rapidity  with  which,  in  conse- 
quence of  its  peculiar  shape,  the  animal  can 
dart  into  the  sand,  whenever  danger  threatens. 
One  species  (Donax  Irus)  perforates  the  hardest 
limestone,  but  by  what  means  it  effects  a  lodg- 
ment in  such  a  substance,  has  not  been  ascer- 
tained ;  pieces  of  stone  are  often  thrown  ashore 
on  the  Devonshire  coast  filled  with  these  shells 
fitting  into  the  apertures  which  they  have  pierced. 
The  shells  of  this  genus  are  generally  of  a  fine 
rich  purple  colour,  sometimes  marked  with  rays 
of  purple  on  a  white  ground.  Many  of  the 
species  are  of  a  yellow  olive  hue.  The  animal 
has  two  long  slender  tubes  not  joined  together, 
and  a  lamellar  foot.  The  Donaces  are  marine 
littoral  shells. 

DONAX  Denticulate.    \  ,., 


Specific  Character.  Shell  strong,  thick,  ovate, 
wedge-shaped,  with  longitudinal  striae,  the  in- 
terstices punctured  ;  *  anterior  slope  rough,  with 
transverse  striae,  and  elevated  in  the  middle  in 
a  kind  of  keel  ;  white  or  lead  colour,  usually 
with  a  few  purple  rays  proceeding  from  the 
urabones,  inside  purple ;  very  concave  under 

*  Punctured,  pricked  or  marked  with  small  dots,  from  the 
Latin  punctww,  a  point  or  dot.  .  v»"  - 


the  umbones;  margin  denticulated;  about  half 
an  inch  long  and  nearly  an  inch  broad. 

This  is  described  as  a  British  species,  but  it 
is  .rarely  found  on  our  coasts.  It  inhabits  the 
West  Indies,  Africa,  and  the  Mediterranean. 

Genus— VENUS— (Plural,  Veneres.) 


Generic  Character.  Shell  bivalve,  equivalve, 
inequilateral,  closed  ;  shape  ovate,  suborbicular, 
or  subcordate  ;  both  the  area  and  areola  are  well 
defined,  the  area  is  generally  flattened,  and  the 
areola  has  often  the  impression  of  a  heart ;  the 
hinge  has  three  approximate  cardinal  teeth, 
the  middle  one  is  longitudinal ,  the  others  diverg- 
ing, there  is  a  lateral  tooth  in  a  few  species  ; 
the  beaks  are  turned  towards  the  areola,  that  is 
from  the  ligament. 


The  shells  of  this  genus,  preeminent  for  the 
elegance  of  their  form,  and  the  beauty  of  their 
colouring,  have  in  consequence,  been  designated 
by  the  name  of  the  fabulous  goddess  of  beauty. 
The  three  approximate  teeth,  and  the  inclination. 

*  Plate  VIII.  figures  7,  8. 

VENUS—  VENUS.  169 

of  the  beaks  towards  the  areola,  at  once  deter- 
mine a  shell  to  be  a  Venus,  but  these  marks  are 
sometimes  wanting ;  in  a  few  species  there  are 
four  cardinal  teeth  in  each  valve,  and  this  is  the 
distinguishing  mark  of  the  genus  separated  from 
this,  under  the  name  Cytherea.  Those  Ve- 
neres  which  have  only  two  teeth  in  each  valve, 
belong  to  the  modern  genus  Crassina. 

The  Venus  is  diffused  over  every  part  of  the 
world,  and  in  many  countries  affords  to  animals 
and  birds  a  nutritious  food.  It  is  curious  to 
observe  the  contrivances  by  which  the  sea-fowl 
endeavour  to  procure  the  mollusks  of  this  and 
other  genera ;  they  have  been  seen  to  take 
advantage  of  a  moment,  when  the  shell  is 
open,  to  drop  a  pebble  between  its  valves, 
which  being  thus  prevented  from  closing,  the  in- 
mate is  left  exposed  to  their  attacks.  Sometimes 
when  they  find  the  shell  so  hard  as  to  resist  all 
their  efforts  to  break  it  with  their  beaks,  they 
ascend  to  some  lofty  eminence,  and  letting  it 
drop  upon  rough  or  craggy  rocks,  it  is  crushed  in 
the  fall,  and  the  animal  thus  becomes  their  prey. 
The  mollusk  of  the  Venus  has  two  siphons 
formed  by  the  mantle,  and  a  lamellar  foot. 

VENUS  Mercenaria. 


Specific    Character.      Shell  ponderous,    ob- 


liquely  heart-shaped,  slightly  striated  trans- 
versely ;  posterior  depression  cordiform  ;  inner 
margin  crenated ;  the  outside  is  greyish  or 
brownish,  the  inside  is  white,  with  a  violet- 
coloured  spot  at  the  anterior  side;  the  length 
is  about  two  inches  and  three-quarters,  the 
breadth  about  three  inches  and  a  half. 

The  Indians  of  North  America  cut  these 
shells  into  beads,  some  white  and  some  black  ; 
of  these  they  form  their  wampum,  or  treaty- 
belts,  which  are  symbolical  of  friendship.  They 
also  string  them  together  and  use  them  for 
money.  The  females  cover  the  shoes  they  wear 
in  dancing  with  these  shells,  which  in  their 
movements  being  struck  together  produce  a 
sound  resembling  the  tinkling  of  the  bells  used 
by  the  Israelitish  women,  and  mentioned  in 
Isa.  iii.  16. 

VENUS  Dysera* 


Specific  Character.  Shell  triangular,  convex, 
heart-shaped,  marked  with  distinct  concentric 
raised  ridges,  which  are  closely  cancellated ;  f 
the  longitudinal  striae  are  also  crossed  by  fine 

*  Plate  VIII.  figure  8. 

"T"  Cancellated,  crossed  like  the  bars  of  a  window,  from 
the  Latin  cancelli,  lattice. 


transverse  lines  ;  margin  crenated  ;  colour  grey, 
or  ivory  white,  variously  marked  with  chesnut 
brown  spots,  the  area  and  areola  are  of  the  same 
colour  as  the  spots  ;  diameter  about  an  inch. 

Found  on  the  shores  of  Germany,  America, 
and  the  East  Indies. 

Genus  -  SPONDYLUS.*— (Plural,  Spondylt. ) 


Generic  Character.  Shell  bivalve,inequivalve, 
inequilateral,  fixed,  strong,  solid  ;  surface  coarse 
and  rough,  with  either  lamellar  or  subulate 
spines  ;  the  hinge  has  two  strong  recurved  teeth 
in  each  valve,  with  an  intermediate  sinus  for  the 
ligament;  the  lower  valve  is  convex,  and  is 
produced  at  the  apex  into  a  projecting  beak 
which  appears  as  if  it  had  been  sliced  off  by  a 
sharp  instrument,  presenting  a  triangular  flattened 
surface,  having  a  groove  which  receives  the 
decaying  part  of  the  ligament.  The  shell  is 
often  eared. 


The  shells  of  this  genus  are  remarkable,  not 
*  Plate  VIII.  figures  9,  10. 


only  for  the  brilliancy  of  colouring,  which  most 
of  them  display,  and  for  the  singularity  of  their 
external  form,  but  also  for  the  clearness  and 
precision  of  the  characters  which  distinguish 
them  from  the  shells  of  other  genera.  The 
roughness  and  irregularity  of  their  appearance, 
their  two  strong  incurved  teeth,  with  the  inter- 
mediate sinus  for  the  ligament,  are  their  discri- 
minative generic  marks.  The  genus  contains 
only  three  species,  one  of  which  has  not  the 
flattened  beak  and  internal  ligament,  and  its 
shells  are  remarkable  for  being  plaited  longi- 
tudinally like  a  fan  half  opened  ;  they  have  been 
separated  by  modern  conchologists  from  the 
Spondylus  under  the  significant  name  of 
Plicatula.*  The  Spondyli  adhere  to  rocks,  co- 
rals, and  other  marine  substances,  at  considerable 
depths  in  the  sea,  they  are  separated  from  them 
with  very  great  difficulty,  they  are  found  often 
in  groups  forming  large  masses.  The  animal 
has  the  edge  of  its  mantle  fringed  with  short 
tentacular  filaments ;  it  has  a  small  radiated 
foot.  From  a  supposed  resemblance  of  the 
Spondylus  to  the  oyster  it  has  been  called  the 
thorny  Oyster  ;  its  scientific  name  is  derived 
from  the  Greek  <nrov$vXos  (spondulos)  the  head 
of  an  artichoke. 

*  Plicatula,  a  little  fold,  from  plica  a  fold.    Plate  VIII. 
figure  10. 


SPONDYLUS  Gcedaropus* 


Specific  Character.  Shell  slightly  curved, 
spinous,  varies  greatly  in  colour,  size,  and  the 
form  of  the  spines,  the  latter  are  generally  lam- 
inated or  tongueshaped,  sometimes  foliated  ;  the 
colour  varies  from  saffron,  to  orange  and  scarlet ; 
the  size  is  about  two  inches  in  diameter. 

It  is  found  adhering  to  rocks  in  the  Mediter- 

Genus— CHAMA.f  (Plural,  Chama.) 


Generic  Character.  Shell  bivalve,  solid  exte- 
rior usually  coarse  ;  hinge  has  a  gibbous  callo- 
sity inserted  obliquely  into  a  corresponding 
sinus  in  the  opposite  valve  ;  this  callosity  or 
tooth  is  either  simple  or  crenated ;  beaks  re- 
curved; form  various. 


This  genus,  as  it  stands  in  the  Linnaean  classi- 
fication, contains  twenty-six  species,  but  some 

*  Plate  VIII.  figure  9.          t  Plate  IX,  figures  1,  2,  3. 


of  these  are  remarkably  dissimilar  in  their  ap- 
pearance. It  includes  regular,  and  irregular, 
equivalve  and  inequivalve  shells,  also  some  that 
are  attached  to  marine  substances,  and  others 
that  are  free.  The  callous  ridge  at  the  hinge  is 
the  most  decided  character  of  the  genus.  The 
name  is  derived  from  wpy  (chem6)  a  gaping, 
and  is  applicable  to  many  of  the  species ;  it  is 
probable  that  all  those  which  have  an  opening 
at  the  margin,  possess  a  byssus,  by  which  they 
are  fastened  to  rugged  substances.  This  genus 
affords  subject  of  amazement  in  the  uncommon 
size  to  which  some  of  its  species  attain.  The 
Giant  Clam  (Chama  Gigas)  is  a  specimen  of 
unusual  magnitude  in  a  shell :  it  is  indeed  the 
largest  of  all  testaceous  productions.  One  of 
these  shells  described  by  Linnaeus,  weighed  four 
hundred  and  ninety-eight  pounds;  and  he  says 
that  its  inhabitant  furnished  one  hundred  and 
twenty  men  with  a  day's  food.  So  great  were 
the  weight  of  the  shell  and  the  strength  of  the 
muscles,  that  by  suddenly  closing  its  valves,  it 
cut  asunder  a  cable.  Another  specimen  brought 
from  Sumatra,  is  preserved  in  Arno's  Vale,  in 
Ireland,  its  weight  is  five  hundred  and  seven 
pounds;  the  largest  valve  measured  four  feet 
six  inches  in  length,  and  two  feet  five  inches  and 
a  half  in  breadth.  A  specimen  of  this  extraox- 
.dinary  species,  forms  a  very  elegant  baptismal 
font  in  the  church  of  St.  Sulpice,  in  Paris,  it 
was  presented  by  the  Venetians  to  Francis  I. 
Large  pearls  are  occasionally  found  in  the 


Chamae ;  one  exhibited  at  Sir  Joseph  Banks', 
was  valued  at  between  two  and  three  hundred 
pounds.  The  colour  of  Chama  Gigas,  is  a 
dingy  white  :  the  ihinge  is  furnished  with  a  car- 
tilage of  a  dull  colour,  which  when  cut  and 
polished,  is  as  beautifully  iridescent  as  Opal. 

CHAMA  Cor* 


Specific  Character.  Shell  equivalve,  globose, 
heart-shaped  when  viewed  from  the  posterior 
side;  thick,  strong,  smooth,  or  only  slightly 
striated  transversely :  umbones  large  and  promi- 
nent, apices  involute,  and  turned  to  one  side  : 
colour  pale  yellowish  brown,  covered  with  a . 
darker  epidermis,  decorticated  at  the  umbones. 
Shell  about  three  inches  long,  and  two  and  three 
quarters  broad. 

This  shell  has  but  very  rarely  been  found  in 
the  British  seas ;  it  is  much  prized  on  account 
of  the  singular  and  graceful  beauty  of  its  form. 

It  belongs  to  the  new  genus  Isocardia. 

CHAMA  Hippopus.  * 

Specific  Character.  Shell  equivalve,  inequi- 
lateral, thick,  heavy,  longitudinally  ribbed  and 

*  Plate  IX.  figure  3.  t  Plate  IX.  figure  2. 


muricated  ;  *  posterior  slope  heart-shaped, 
closed  ;  margin  in  front  deeply  sinuous ;  the  co- 
lour is  white  or  yellowish,  with  scattered  reddish 
or  purplish  spots ;  commonly  about  two  inches 
long,  and  three  inches  and  a  quarter  inside,  but 
it  sometimes  occurs  double  this  size. 

It  inhabits  the  East  Indian  ocean.  • 

Genus— ARC  A.f  (Plural,  Areas.) 

Generic  Character.  Shell  bivalve,  equivalve, 
inequilateral ;  form  various,  often  oblong,  some- 
times orvicular  ;  hinge  with  numerous  small 
sharp  teeth  in  each  valve,  alternately  inserted 
between  each  other,  arranged  sometimes  in  a 
straight,  sometimes  in  a  curved  line  ;  beaks  ge- 
nerally remote ;  ligament  external. 


The  shells  of  this  genus  are  very  readily 
known,  by  their  numerous  small  teeth.  Some 
of  the  species  attach  themselves  to  rocks  by  a 
kind  of  byssus :  these  have  always  the  shell  more 
or  less  gaping  ;  but  the  greater  part  of  the  Arks 
live  buried  in  the  sand  at  a  short  distance  from 

*  Muricated,  having  little  pointed  knots,  from  the  Latin 
murex,  the  sharp  point  of  a  rock. 

f  Plate  IX.  figures  4,  5,6. 

ARCA—  ARK.  177 

the  shore  ;  all  are  marine.  The  mollusk  has 
no  external  siphons,  it  has  a  kind  of  compressed 
peduncle,  terminated  by  tendinous  filaments, 
which  are  affixed  to  rocks.  The  shells  of  this 
genus  which  have  the  teeth  arranged  in  a  curved 
line,  have  been  formed  into  a  new  genus  called 
Pectunculus;  *  their  form  is  orbicular,  and 
they  are  not  attached  to  rocks, 


Specific  Character.  Shell  oblong,  roundish  at 
one  end,  elongated  at  the  other,  narrow,  and 
inclining  to  angular  ;  beaks  lateral,  remote  from 
each  other,  the  apices  incurved  with  a  broad 
smooth  space  between  them  ;  teeth  in  a  straight 
line  ;  surface  strongly  striated  longitudinally, 
and  crossed  with  transverse  lines  ;  margins  sinu- 
ous and  somewhat  gaping  ,  of  a  pale  rufous 
colour,  with  dark  oblique  bands  ;  the  broad 
flat  space  between  the  apices  has  a  few  distant 
grooves  radiating  from  the  umbones  ;  length 
about  an  inch,  breadth  two. 

This  singular  shell  much  resembles  the  hulk 
of  a  ship  ;  the  flattened  area  and  areola  may  be 
considered  as  the  deck,  the  pointed  end  the  prow, 
the  gibbous  and  rounded  end  the  stern,  and  the 
acute  edge  of  the  united  margins  has  the  appear-. 

*  Plate  IX.  figure  5.  f  Plate  IX.  figure  6. 



ance  of  the  keel.  The  form  of  the  shell 
suggested  the  name  of  Noah's  Ark,  and  from 
this  fancied  resemblance  in  one  species  to  the 
ark,  the  genus  owes  its  designation. 

This  shell  is  affixed  to  rocks  by  a  very  strong 
tendinous  substance,  there  is  an  open  space  in  the 
front  of  the  valves,  through  which  it  issues. 

It  inhabits  the  Mediterranean,  Indian  ocean, 
West  Indies,  and  Britain. 

ARCA  Undata* 


Specific  Character.  Shell  suborbicular,  nearly 
smooth,  with  faint  reticulated  f  striae  ;  margin 
crenated  ;  teeth  in  a  curved  line  ;  colour  white, 
variegated  with  yellowish  red  spots,  in  undu- 
lated transverse  bands. 

Inhabits  the  West  Indies,  and  shores  of  Italy. 
It  belongs  to  the  modern  genus  Pectunculus. 

*  Plate  IX.  figure  5. 

f  Reticulated,  having  the  appearance  of  net  work,  from 
the  latin  reticulum,  a  small  net. 


Genus— OSTREA.*— (PZwraZ,  Ostrecs.) 


Generic  Character.  Shell  bivalve,  generally 
inequi valve,  inequilateral,  more  or  less  eared  ; 
hinge  without  teeth,  having  an  ovate  sinus,  in 
which  is  fixed  an  elastic  cartilage,  and  generally 
lateral  transverse  grooves. 


This  genus  contains  shells  very  different  in 
their  general  appearance,  but  united  by  the 
peculiarity  in  the  hinge,  which  is  toothless,  and 
has  an  elastic  cartilage  inserted  into  a  sinus.  It 
may  be  divided  into  two  families,  the  Pecten  or 
Scallop,  and  the  Oyster,* which  are  separated 
by  very  marked  distinctions. 

The  Pecten  is  of  a  regular  orbicular  form, 
and  eared ;  its  surface  is  adorned  with  diver- 
gent ribs,  which  proceed  from  the  apices  to 
the  circumference,  where  they  terminate  in  a 
scalloped  margin.  The  shells  of  this  division 
usually  display  brilliant  colours. 

The  second  division  contains  the  species  more 
or  less  resembling  the  common  oyster;  these 

*  Plate  IX.  figures  7,  8: 
N  2 


shells  are  irregular  in  their  form,  have  a  rugged 
and  laminated  exterior,  with  one  valve  more  con- 
cave than  the  other,  are  generally  without  ears, 
and  their  colour  is  grey  or  black. 

The  Pectens  are  described  as  possessing  asto- 
nishing powers  of  locomotion,  considering  the 
inferiority  of  their  organization  ;  but  dexterity 
and  ingenuity  frequently  compensate  for  natural 
deficiency.  They  have  the  power  of  progressive 
motion,  both  on  land  and  in  the  water.  When 
the  animal  happens  to  be  left  on  the  shore  by 
the  retiring  tide,  it  opens  its  valves  to  their 
full  extent,  and  closing  them  with  great  mus- 
cular power,  is  thrown  forward  five  or  six 
inches  by  a  sudden  leap.  In  this  manner  it 
reaches  the  sea  ;  should  the  weather  be  calm,  it 
raises  one  of  its  valves,  which  catching  the  breeze, 
acts  as  a  kind  of  sail,  while  the  other  resting  on 
the  surface,  supports  the  floating  animal ;  when 
danger  threatens,  the  shell  is  closed,  and  sinks 
securely  to  the  bottom  of  the  sea.  Many  of  the 
Pectens  possess  the  power  of  forming  threads,  by 
which  they  anchor  themselves  to  floating  timber, 
and  by  this  means  find  protection  when  the  sea 
is  agitated  by  storms  and  tempests.  These 
varied  means  of  escaping  danger  are  no  doubt 
afforded  as  a  necessary  protection  against  their 
numerous  enemies.  The  pilgrims  who  in  former 
days  visited  Jerusalem,  to  pay  their  devotions 
at  the  holy  sepulchre,  on  their  return  wore 
these  shells  in  their  caps  as  trophies  of  their 
achievement  in  crossing  the  sea  for  this  sacred 


purpose  ;  and  in  commemoration  of  this  super- 
stitious act  of  devotion,  it  was  often  granted  them 
to  have  Pectens  engraved  in  their  coats  of  arms, 
that  a  record  of  their  religious  zeal  might  be 
handed  down  to  posterity. 

The  shells  of  the  second  division  differ  from 
the  Pectens  as  much  in  their  habits  as  in  their 
appearance.  They  are  reputed  to  be  some 
of  the  most  sluggish  of  animals,  and  to  have  very 
limited  powers  and  faculties ;  but  whilst  we 
cannot  fail  to  observe  this  destitution,  we  trace 
the  goodness  of  the  Creator,  who  has  placed  them 
in  situations  not  exposed  to  danger,  and  bestowed 
upon  them  an  organization  that  requires  but 
little  to  satisfy  it.  The  only  nourishment  they 
need  is  brought  to  them  by  the  ever-flowing 
waves,  and  they  scarcely  exhibit  any  symptom 
o  life,  but  that  of  opening  their  valves  to 
receive  the  water,  and  then  closing  them  for 
security.  Firmly  attached  to  the  rocks,  and 
enclosed  within  their  strong  testaceous  dwelling, 
they  are  protected  against  surrounding  dangers. 
They  sometimes  effect  a  change  in  their  posi- 
tion by  a  curious  contrivance  ;  they  manage  to 
bolster  up  one  valve  in  the  sand  or  mud,  and 
having  thus  fixed  themselves  erect,  they  open 
their  shells,  and  the  flowing  or  reflux  of  the  tide 
forces  them  over  by  the  pressure  of  the  water. 
The  animal  has  neither  siphon  nor  foot. 


OSTREA  Edulis. 


Specific  Character.  Shell  more  or  less  orbicu- 
lar, inclining  to  oval,  but  subject  to  much  vari- 
ation in  form  and  size,  imbricated  with  scaly 
laminae ;  upper  valve  small  and  flattened,  the 
other  convex ;  inside  pearly  white,  outside  dull 

Oysters  are  generally  found  with  their  lower 
valves  fixed  to  rocks  or  loose  stones,  and  fre- 
quently to  one  another.  Most  of  our  rocky 
coasts  abound  with  these  shells,  but  Essex  and 
Suffolk  chiefly  are  celebrated  for  them.  They 
are  dredged  up  by  a  kind  of  net,  with  an  iron 
scraper  at  the  mouth,  and  are  immediately 
stowed  in  pits  formed  for  the  purpose  in  the 
salt  marshes,  which  are  overflowed  only  at  spring 
tide,  and  from  which  sluices  let  the  salt  water 
escape,  retaining  a  depth  of  about  eighteen  feet. 
The  water  being  stagnant,  in  warm  weather  it 
becomes  green,  and  in  a  few  days  the  oysters 
acquire  the  same  tinge ;  they  are  then  held  in 
great  estimation  in  the  market,  but  they  do  not 
attain  their  greatest  perfection  under  six  or  eight 

Oysters  are  not  considered  fit  for  the  table  till 
they  are  about  a  year  and  half  old,  and  the  fish- 
ermen know  their  age  by  the  increase  in  the  size 
of  the  distance  which  separate  the  circles  of 
laminae  in  the  convex  valve.  When  young 


shells  happen  to  be  taken,  they  are  always 
rejected  and  cast  back  into  the  sea.  Great 
Britain  has  for  many  ages  been  noted  for  its 
oysters,  which  in  former  times  were  sent  as  a 
peculiar  delicacy  to  the  epicures  of  Rome. 

OSTREA  Malleus* 


Specific  Character.  Shell  flexuous,  elongated 
at  the  base,  often  produced  into  two  lobes  giving 
it  somewhat  the  form  of  a  hammer,  from  whence 
it  derives  its  name  ;  outside  imbricated  with 
scaly  laminae  ;  the  colour  generally  dark  grey 
or  blackish  ;  inside  very  glossy,  pearly,  and 
tinged  with  blue ;  it  is  about  five  or  six  inches 
long,  and  four  or  five  across  from  the  extremities 
of  the  two  lateral  lobes. 

This  shell  is  much  prized  on  account  of  its 
very  singular  appearance.  It  is  found  in  the 
Indian  Ocean  :  its  animal  forms  a  byssus  which 
passes  through  a  small  opening  in  the  shell  near 
the  beaks.  It  now  is  arranged  in  the  genus 

PECTEN  Maximus. 


Specific   Character.     Shell  inequivalve  with 

*  Plate  IX.  figure  8.  "    . 


equal  auricles  ;  upper  valve  flattish,  depressed 
near  the  hinge,  lower  valve  convex  ;  the  sur- 
face has  about  fourteen  rounded  ribs,  is  longi- 
tudinally grooved,  and  very  finely  striated  trans- 
versely ;  the  lower  valve  is  white,  tinged  with 
red  ;  upper  valve  reddish  brown  or  spotted  with 
pink  and  brown  ;  inside  white  with  a  reddish 
brown  margin  ;  length  five  inches,  breadth  six. 
This  shell  is  not  uncommon  on  some  of  our 
coasts,  particularly  at  the  mouth  of  large  rivers ; 
it  is  frequently  sold  for  the  use  of  the  table,  and 
is  much  esteemed  as  a  nutritious  diet.  It  is 
asserted  by  fishermen,  that  they  are  taken  in  the 
greatest  quantities  after  a  fall  of  snow.  This 
was  the  species  worn  by  the  Pilgrims  who  visited 
the  Holy  Land. 

Genus-ANOMIA.*    (Plural,  Anamia.) 


Generic  Character.  Shell  bivalve,  inequivalve, 
form  suborbicular,  one  valve  flattened,  and  often 
perforated  in  the  disk,  the  other  more  concave,, 
and  sometimes  having  its  beak  produced  and 
curved  over  the  hinge,  and  perforated  at  the 
apex  ;  hinge  toothless,  having  a  linear  projection 
which  is  united  under  the  beak  to  the  opposite 
valve  by  a  strong  ligament. 

*  Plate  IX.  figure  9 ;  Plate  X.  figure  1. 



This  genus  contains  a  variety  of  shells  mate- 
rially differing  in  their  appearance.  The  perfor- 
ation in  one  of  the  valves  for  the  emission  of  a 
ligament,  by  which  the  animal  adheres  to  marine 
substances,  is,  perhaps,  the  most  general,  though 
not  an  invariable  characteristic. 

The  Anomiae  are  now  arranged  in  two  prin- 
cipal groups,  very  clearly  distinguished  from 
each  other.  The  shells  of  one  division  retain  the 
name  of  Anomia,  and  very  much  resemble  a 
small  oyster  in  their  appearance  ;  like  them  they 
are  fixed  and  stationary,  living  and  perishing  on 
the  spot  where  the  egg  was  first  deposited. 
They  are  attached  by  means  of  a  bony  appen- 
dage, having  a  dilated  base  ;  this  is  in  fact  only 
a  prolongation  of  the  adductor  muscle  of  the 
animal  ossified  at  its  outer  extremity.  When 
the  mollusk  contracts  the  muscle,  the  dilated 
portion  is  drawn  over  the  perforation  of  the 
flattened  valve  and  covlrs  it,  acting  as  an  oper- 
culum.  So  firmly  are  the  shells  fixed  by  this 
organ,  that  they  cannot  be  removed  from  their 
retreat,  without  destructive  violence,  the  liga- 
ment and  operculum  being  left  on  the  rock  to 
which  they  were  cemented.  The  form  of  the 
Anomia,  like  that  of  all  stationary  shells,  is  very 
irregular,  being  usually  modified  by  the  sub- 
stances to  which  it  adheres.  The  prevailing  co- 


lour  of  this  genus  is  a  dingy  yellow,  or  dusky 
white;  the  shells  are  generally  thin,  fragile, 
delicate,  and  would  be  ill-fitted  to  contend  with 
the  dangers  of  their  dwelling  in  the  boisterous 
ocean,  had  not  He  who  placed  them  amidst  its 
perils,  exercised  his  compensatory  providence, 
and  anchored  them  securely  in  its  depths.  The 
animal  belonging  to  the  shells,  is  very  similar  to 
the  oyster. 

The  other  family  of  this  genus  now  bears  the 
name  of  Terebratula.  The  shells  which  it  con- 
tains, are  distinguished  by  the  graceful  elegance 
of  their  form,  which  resembles  a  Grecian  lamp, 
and  from  hence  they  are  called  the  Antique 
Lamps.  The  concave  valve  of  the  Terebratula 
has  its  beak  produced,  curved  over  the  other 
valve,  and  perforated  at  the  apex ;  the  smaller 
valve  is  furnished  with  two  slender  shelly  pro- 
cesses, which  are  sometimes  short,  simple,  and 
recurved  ;  sometimes  long,  branching  and  cross- 
ing each  other  ;  their  use  is  not  ascertained,  but 
it  is  supposed  that  they  are  supports  for  the  ani- 
mal. The  Terebratulae  inhabit  the  depths  of 
the  ocean ;  they  are  parasitical,  and  are  attached 
to  various  submarine  substances  by  a  tough  short 
stalk  which  differs  from  the  ligament  of  the 
Anomia  in  being  formed  of  numerous  closely 
united  fibres,  separating  a  little  at  the  end,  by 
which  they  are  fixed.  The  mollusk  which  in- 
habits this  shell  is  remarkable  for  two  long 
fringed  arms,  rolled  up  in  a  spiral  form  within 
the  shell  when  at  rest,  but  which  it  protrudes 
when  hunger  prompts  it  to  seek  for  food. 


ANOMIA  EpUppium.* 


Specific  Character.  Shell  suborbicular,  irre- 
gular, wrinkled,  sinuous  at  the  margin ;  inside 
pearly  and  iridescent;  colour  yellow,  reddish  or 
white :  varies  from  two  to  three  inches  in 

This  shell  belongs  to  the  division  still  bearing 
the  name  of  Anomia.  It  adheres  to  other 
bodies,  and  particularly  oysters,  and  receives 
the  impression  of  the  substances  to  which  it  is 
affixed,  its  form  being  modelled  by  the  circum- 
stances under  which  it  adds  to  its  size.  Some 
specimens  have  been  taken  from  the  Pecten 
Maxim  us  exhibiting  clearly  the  impression  of 
its  ribs. 

ANOMIA  Psittacea.  f 


Specific  Character.  Shell  oval,  horny,  pel- 
lucid; the  beak  much  produced,  curved,  and 
perforated,  the  hole  sub  triangular  ;  margin  sinu- 
ated,  entire;  surface  finely  striated  longitudi- 
nally ;  colour  is  blackish,  or  greenish  brown ; 
length  about  three  quarters  of  an  inch,  exceeding 
the  breadth. 

This  shell  belongs  to  the  Terebratulae :  it  in- 
habits the  Indian  Sea,  and  Greenland. 

*  Plate  X.  figure  1.  t  Plate  IX.  figure  10. 


Genus— MYTILUS.*  (Plural,  Mytili.) 


Generic  Character.  Shell  bivalve,  rough, 
generally  affixed  by  a  byssus  to  marine  sub- 
stances ;  shape  generally  a  long  oval,  sometimes 
lobed,  sometimes  elongated  at  the  beaks  ;  hinge 
mostly  without  teeth,  marked  by  a  furrow  or 
by  a  subulate  line,  which  is  crenated  in  some  of 
the  species. 


Though  all  the  Mytili  are  not  inseparably 
attached  to  other  subtances,  all  are  by  some 
means  rendered  stationary  ;  the  silky  filaments 
produced  by  some  of  the  species  are  entwined 
in  the  coralines  and  stones  at  the  bottom  of  the 
sea,  and  securely  anchor  the  group  of  muscles 
found  there.  Others  of  the  species  perforate 
rocks  or  even  large  shells,  and  form  for  them- 
selves at  once  their  residence  and  grave.  The 
Mytili  which  have  their  beaks  nearly  terminal 
and  pointed,  and  are  of  a  dark  colour,  much 
resemble  a  mouse,  and  from  the  circumstance 
of  a  few  species  being  like  this  animal,  the 
genus  has  received  its  name,  which  is  derived 

*  Plate  X.  figure  2. 


from  {AtmXo?  (mutilos)  the  diminutive  of  pv$ 
(mus)  a  mouse.  Some  of  the  species  have  their 
base  elongated  with  lobes  on  each  side,  and  bear 
a  resemblance  to  a  bird  in  full  flight.*  The 
name  Mytilus  is  now  confined  to  the  shells 
whose  beaks  are  terminal. 

MYTILUS  Edulis.  f 


Specific  Character.  Shell  oval,  pointed  at  the 
beaks ;  sides  much  sloped,  flattish  at  the  an- 
terior, and  rather  angular  and  carinate  at  the 
posterior  end  ;  hinge  terminal  ;  beneath  the 
margin  are  several  tooth-like  crenulations ;  colour 
often  of  a  rich  blue  when  deprived  of  its  epider- 
mis which  is  brown;  inside  blue  about  the 
margin,  and  whitish  in  the  middle,  length  from 
two  to  three  inches,  and  about  half  as  broad. 

This  shell  is  the  most  common  of  all  the 
British  species,  and  is  found  in  large  beds, 
attached  by  a  byssus.  The  mollusks  have  a 
tongue-shaped  muscular  foot,  capable  of  great 
powers  of  elongation  and  contraction  ;  with  this 
instrument  they  are  able  to  effect  a  progressive 
motion.  Forming  a  furrow  in  the  sand,  and 
placing  their  shell  erect,  they  stretch  out  the 
foot,  which  being  rather  viscid,  adheres  to  the 
ground,  and  when  an  effort  is  made  to  contract  it, 

*  Plate  X.  figure  3.  t  Plate  X.  figure  2. 

190  •  BIVALVES. 

the  shell  is  drawn  along  the  groove.  Thus 
alternately  extending  and  contracting  this  mus- 
cular instrument,  the  Mytilus  contrives  to  creep 
to  a  convenient  situation  for  anchorage,  and  by 
means  of  this  same  foot  it  then  forms  a  coarse 
byssus,  which  fixes  it  to  the  chosen  spot.  Often 
towards  the  end  of  autumn  a  little  crab  is  found 
sheltering  itself  within  the  valves  of  the  muscle. 
This  little  creature  is  called  the  Pisum,  or  Pea 
Crab :  it  is  supposed  so  have  been  placed 
in  the  shell  of  the  Mytilus  and  other  Bivalves, 
to  assist  by  its  sagacity,  the  more  limited  powers 
of  its  host,  whom  it  repays  for  a  safe  retreat, 
by  going  in  search  of  provender,  and  sharing  it 
with  him. 

MYTILUS  Margaritiferus. 


Specific  Character.  Shell  suborbicular,  com- 
pressed, the  margin  rounded,  except  on  the 
hinge  side  where  it  is  straight  and  transverse  ; 
surface  imbricated  with  transverse  membra- 
naceous  scales,  having  the  laminae  toothed  in 
rays ;  colour  commonly  greenish  or  pale  ches- 
nut,  inside  pearly  and  iridescent ;  the  full 
grown  shells  are  sometimes  ten  or  twelve  inches 
long  and  rather  less  in  breadth :  they  are  thick, 
and  ponderous,  but  young  specimens  are  thin, 
brittle,  and  slightly  eared. 

*  Plate  X.  figure  3. 


This  species  now  forming  the  genus  Melagrina, 
is  much  celebrated  for  producing  pearls.  They 
are  thought  to  be  occasioned  by  a  disease  in  the 
Mollusk,  and  to  be  produced  by  a  partial 
secretion  of  the  substance  of  which  it  forms  the 
inner  coating  of  its  shell ;  it  is  arranged  in  the 
pearl  in  concentric  layers.  Acids,  have  the 
same  effect  upon  pearls  as  upon  other  carbonates 
of  lime,  and  Cleopatra  is  said  to  have  dissolved  in 
vinegar  one  of  great  value  in  order  to  display 
her  magnificence  by  this  costly  draught.  The 
pearl  fishery  is  a  very  dangerous  employment  ; 
it  is  principally  carried  on  in  the  Persian  Gulph 
and  the  neighbourhood  of  Ceylon  ;  the  season 
for  the  fishery  lasts  about  a  fortnight.  Numer- 
ous boats  are  dispatched  to  the  station  where  it 
is  carried  on,  each  containing  twenty  men,  ten 
of  whom  are  employed  in  rowing  and  assisting 
the  divers.  They  descend  alternately  in  parties 
of  five,  and  thus  time  is  afforded  for  all  to 
recover  themselves  after  their  violent  exertion. 
The  diver  has  a  rope  attached  under  his  arms, 
the  end  of  which  is  given  to  the  men  in  the 
boat ;  round  his  neck  is  slung  a  net,  distended 
at  the  opening  by  a  hoop.  Closing  his  nostrils, 
he  commits  himself  to  the  sea,  with  a  perforated 
stone  of  ten  or  twenty  pounds  weight  affixed  to 
his  foot,  to  accelerate  his  descent.  He  sinks 
generally  a  depth  of  twenty  or  thirty  yards; 
then  quickly  proceeding  to  his  work,  he  tears 
the  muscles  from  their  bed,  fills  his  net,  makes 
a  signal  and  is  drawn  up  again  to  the  surface. 


Many  and  great  are  the  dangers  attendant  on 
this  employment.  The  greedy  shark  often 
marks  the  diver  for  his  prey,  his  only  chance  of 
safety  under  such  circumstances,  is  by  muddy- 
ing the  water,  and  so  eluding  the  animal's  obser- 
vation. A  large  flat  fish  also  sometimes  attacks 
him,  and  keeps  him  under  water  till  he  is  drowned. 
When  drawn  up  in  safety  to  his  vessel,  he  often 
in  consequence  of  his  exertion  discharges  blood 
from  his  mouth  and  nostrils.  The  divers  rest 
and  labour  alternately,  during  periods  of  about 
ten  minutes. 

Genus— PINNA— (Plural,  Pinna.) 

Generic  Character.  Shell  bivalve,  equivalve, 
fragile,  thin,  gaping  at  one  end,  and  furnished 
with  a  byssus ;  shape  subtriangular,  narrow  at 
the  beaks,  and  expanding  to  a  considerable 
breadth  at  the  opposite  extremity  ;  hinge  with- 
out teeth  ;  valves  united  by  a  long  external 

*  Plate  X.  figure  3. 


—SEA  WING.  193 


The  Pinna  seems  to  form  the  connecting  link 
between  the  univalves  and  bivalves,  for  though 
it  is  composed  of  two  valves,  yet  it  is  incapable 
of  moving  on  its  hinge.  It  is  generally  found  at  a 
short  distance  from  the  shore,  fixed  in  the  mud 
at  its  smaller  end,  and  standing  erect.  The  ani- 
mal forms  abyssus,  the  fibres  of  which  are  ag- 
glutinated, to  the  sand,  gravel,  roots  of  marine 
plants,  broken  shells,  or  any  matter  within  its 
reach.  The  byssus  of  the  Pinna  is  much  more 
fine  and  delicate  than  that  of  the  muscle  ;  the 
filaments  are  long,  silky,  and  of  a  bright  lustre  ; 
the  natural  colour  is  of  a  rich  golden  brown,  but 
it  readily  receives  any  tint.  The  animal  pos- 
sesses a  kind  of  tubular  instrument,  furnished 
with  a  gland  which  secretes  a  glutinous  sub- 
stance :  by  means  of  a  slight  pressure,  a  drop 
of  this  liquid  is  deposited  on  the  spot,  to  which 
the  byssus  is  to  be  attached  ;  by  the  retraction 
of  the  foot,  a  silken  filament  is  drawn  out,  and 
this  operation  being  repeated  some  thousands  of 
times,  a  beautiful  tuft  of  silky  fibres,  is  pro- 
duced. The  Pinnae  are  much  sought  after  on 
the  coasts  of  Sardinia  and  Corsica  for  the  sake 
of  the  byssus;  they  are  fished  up  with  an  instru- 
ment which  consists  of  two  semicircular  bars  of 
iron  fastened  together  at  each  end,  but  three 


inches  distant  from  each  other  at  the  centre.  At 
one  end  is  a  hollow  handle,  in  which  a  pole  is 
fixed,  at  the  other  is  a  ring,  to  which  a  cord  is 
fastened.  When  a  Pinna  is  discovered,  the  iron 
is  let  down  slowly  over  the  shell,  which  is  then 
twisted  round  and  drawn  out.  When  a  suffi- 
cient number  have  been  caught,  the  silk  is  cut 
off,  and  after  being  twice  soaked  in  tepid  water, 
and  once  in  soap  and  water,  is  spread  out  to  dry 
in  some  cool  and  shady  place.  Whilst  it  is  yet 
moist,  it  is  again  softly  rubbed  and  separated 
with  the  hand,  and  then  spread  out  again.  When 
thoroughly  freed  from  moisture,"  it  is  drawn 
through  a  comb  with  the  teeth  wide  apart,  and 
afterwards  through  a  similar  instrument,  with 
finer  and  closer  teeth.  The  more  common  silk 
is  thus  prepared,  but  that  which  is  destined  for 
finer  works,  is  afterwards  drawn  through  closer 
iron  combs  or  cards.  It  is  spun,  two  or  three  of 
the  threads  being  mixed  with  one  of  real  silk, 
and  then  knitted  into  gloves,  stockings,  and 
even  whole  garments.  When  the  piece  is  knitted, 
it  is  washed  in  clean  water  mixed  with  lemon 
juice,  gently  beaten  between  the  hands,  and 
smoothed  with  a  warm  iron.  The  shells  of  the 
Pinna  are  often  ornamented  with  elevated  longi- 
tudinal ribs,  crossed  by  striae,  sometimes  ter- 
minated by  imbricated  arched  scales,  or  pro- 
minent tubular  spines.  Some  of  the  young 
shells  of  this  genus  are  less  than  an  inch  in 
length,  whilst  the'adults  often  exceed  three  feeti 
The  Pinna  as  well  as  the  Muscle,  was  much 


celebrated  by  the  ancients  ;  they  supposed  it  to 
harbour  within  its  shell  a  small  crustaceous 
animal,  a  kind  of  shrimp,  which  was  said  to  be 
of  the  greatest  use  to  its  companion,  by  warning 
it  of  the  vicinity  of  the  prey  upon  which  it 
subsists,  or  of  the  approach  of  its  great  enemy 
the  Sepia.  Many  stories  are  related  of  the 
amiable  habits  of  this  pair,  and  of  the  mutual 
services  they  render  each  other.  The  truth  of 
these  accounts  are  much  confirmed  by  small  ani- 
mals of  the  crustaceous  tribe  being  continually 
found  in  the  shells  of  the  Pinna  and  Muscle. 
The  ancients  have  celebrated  these  histories,  by 
making  them  the  subject  of  poetry  ;  the  follow- 
ing verses  are  translated  from  a  latin  author,  and 
are  very  descriptive  of  the  habits  of  the  Pinnse. 

In  clouded  deeps  below  the  Pinna  hides, 
And  through  the  silent  path  obscurely  glides  ; 
A  stupid  wretch,  and  void  of  thoughtful  care, 
He  forms  no  bait,  nor  lays  the  tempting  snare  ; 
But  the  dull  sluggard  boasts  a  crab  his  friend, 
Whose  busy  eyes  the  coming  prey  attend. 
One  room  contains  them,  and  the  partners  dwell 
Beneath  the  convex  of  one  sloping  shell  ; 
Deep  in  the  watery  vast  the  comrades  rove, 
And  mutual  interests  binds  their  constant  love. 
That  wiser  friend  the  lucky  juncture  tells, 
When  in  the  circuit  of  the  gaping  shells 
Fish,  wandering,  enter ;  then  th*  bearded  guide, 
Warns  the  dull  mate,  and  pricks  his  tender  side  ; 
He  knows  the  hint,  nor  at  the  treatment  grieves, 
But  hugs  the  advantage,  and  the  pain  forgives : 
His  closing  shells  the  Pinna  sudden  joins, 
And  'twixt  the  pressing  sides  his  prey  confines. 
Thus  fed  by  mutual  aid  the  friendly  pair 
Divide  their  gains,  and  all  their  plunder  share. 
O  2 

196  MVALVES. 

The  name  Pinna,  which  is  sometimes  spelled 
with  one  n,  is  supposed  to  be  derived  from  nuo<; 
(pinos)  the  dirt  or  mud ;  but  the  name  given  it 
by  British  conchologists  would  lead  us  to  take 
its  derivation  from  the  Latin,  pinna,  a  large 

PINNA  Pectinate.* 


Specific  Character.  Shell  triangular,  oblong, 
with  about  eleven  longitudinal  ribs,  having  con- 
cave spines,  which  increase  in  size  as  they 
approach  the  broadest  end  ;  the  other  side  desti- 
tute of  ribs,  but  obliquely  striated ;  shell  thin, 
pellucid,  brittle,  of  a  light  brown  colour,  darker 
towards  the  beaks ;  inside  of  a  pearly  hue  ; 
breadth  three  inches  at  the  gaping  end,  which 
is  slightly  rounded  ;  length  six  inches  and  a 
half.  This  shell  inhabits  India  ;  it  has  also  been 
found  on  the  coasts  of  Dorset  and  Sussex. 


1.  Describe  the  part  of  a  Bivalve  shell  which 
unites  the  two  valves. 

2.  By  what  means  are  the  animals  able  to 
open  these  valves  ? 

*  Plate  X.  figure  4. 


3.  What  is  the  meaning  of  the  terms  equivalve, 
inequivalve,  equilateral,  inequilateral,  and  what 
is  their  derivation  ? 

4.  Describe   the  mollusk  inhabiting  bivalve 
shells  ? 

5.  How  is  the  generic  character  of  bivalve 
shells  determined  ? 

6.  Name  the   parts  of  a  bivalve  shell,  and 
describe  the  situation  of  each  part. 

7.  What  is  the  generic  character  of  the  Mya, 
and  what  are  its  distinguishing  marks  ? 

8.  Describe  the  manner  in  which  the  shell  of 
the  Mya  Margaratifera  is  peculiarly  suited  to 
the  situations  it  occupies. 

9.  What  are    pearls,  and  in   what  kind    of 
shells  are  they  found  ? 

10.  What   is   the  generic  character   of   the 
Solen,  and  how  is  it  distinguished  ? 

11.  Describe  the  habits  of  the  Solen. 

12.  What   is   the   generic   character   of    the 
Tellina,  and  its  distinguishing  mark  ? 

13.  What   is    the   generic  character  of    the 
Cardium,  and  its  distinguishing  marks  ? 

14.  Which  species  of  tne  Cardium  afford  food 
to  the  poorer  classes  ? 

15.  What  is  the  general  appearance  of  the 
Mactrae  ? 

16.  What  is  the  generic  character   of   the 
Donax  ? 

17.  What  is  the   generic    character    of  the 
Venus,  and  its  distinguishing  mark  ? 

18.  To  what  use   is  the  Venus   Mercenaria 
converted  ? 


19.  What  is   the   generic   character   of   the 
Spondylus  ? 

20.  What  is    the   generic  character   of    the 
Chama,  and  its  distinguishing  mark  ? 

21.  Give  an  account  of  the  Chama  Gigas  ? 

22.  What  is  the  generic  character  of  the  Area, 
and  its  distinguishing  mark  ? 

23.  What  difference  occurs  in  the  arrange- 
ment of  the  teeth  of  the  Area  ? 

24.  What  is  the   generic   character   of   the 
Ostrea,  and  its  distinguishing  mark  ? 

25.  Describe   the    two    great    families    into 
which  the  Ostrea  is  divided. 

26.  Describe  the  difference  in  the  habits  of 
the  Pecten  and  the  Oyster. 

27.  Describe  the  manner  of  taking  and  fat- 
tening the  common  oyster. 

28.  What    is  the  generic   character   of    the 
Anomia  ? 

29.  Describe  the  two  families  into  which  the 
Anomia  is  divided. 

30.  What    is  the   generic  character   of  the 
Mytilus  ? 

31.  Describe  the  habits  of  the  common  mus- 

32.  Describe  the  pearl  fishery. 

33.  What   is   the  generic    character  of    the 
Pinna  ? 

34.  Why  is  the  Pinna  considered  as  a  link 
between  the  univalves  and  bivalves  ? 

35.  Describe  the   habits  of  the  animal  inha- 
biting the  Pinna. 



This  class   according   to  Linnaeus,    contains 

three  genera.     The  generic  character  is  chiefly 

determined  by  the  number  of  valves  and  their 

Genus.— PHOLAS.*— (Plural.  PMades.) 


Generic  Character.  Shell  with  two  primary 
valves  gaping  at  both  ends,  and  several  smaller 
accessory  valves  situated  upon  the  hinge  and 
posterior  slope ;  hinge  recurved,  each  valve  has 
a  long  tooth  curved  towards. 


The  shells  of  this  genus  are  thin,  fragile,  and 
usually  either  of  a  pure  or  dusky  white,  adorned 
with  beautiful  minute  fret  work  :  the  reticulations 
in  some  species  are  so  delicate  and  fine  as  to  re- 
semble lace;  in  others,  they  are  coarser,  and 
approaching  to  small  basket  work.  The 

*  Plate  X.  figure  8. 


Pholades  were  ranked  by  Linnaeus  amongst  the 
multivalves,  but  by  modern  conchologists  they 
are  generally  placed  with  the  bivalves.  The 
two  principal  valves  connected  by  a  hinge, 
associate  them  closely  to  the  latter,  and  the 
small  testaceous  plates  around  the  hinge  may 
be  considered  as  mere  appendages,  for  they  do 
not  act  the  part  of  valves.  The  Pholas  appear 
the  connecting  link  between  the  classes  of 
bivalves  and  multivalves.  So  gradual  are  the 
steps  by  which  the  scale  of  nature  proceeds,  that 
it  is  often  difficult  to  ascertain  precisely  the 
line  which  separates  its  great  divisions, 

The  Pholades  are  all  borers,  perforating  wood, 
clay,  limestone,  and  sometimes  burying  them- 
selves in  the  sand,  forming  a  retreat  in  which  they 
pass  their  lives.  The  name  marks  their  peculiar 
propensity,  being  derived  from  (puXeos,  (pholeos) 
a  hiding  place.  The  largest  species,  and  the  finest 
specimens  are  most  frequently  found  in  chalk, 
which  being  the  softest  of  calcareous  substances, 
admits  of  a  more  easy  and  rapid  progress  to  the 
animal  than  the  indurated  stones  in  which  they 
are  sometimes  discovered.  How  they  effect 
their  lodgment,  is  still  a  subject  of  doubt  and 
inquiry.  Many  have  supposed  that  a  continued 
rotatory  *  motion  would  in  time  produce  such  a 
cavity  as  they  inhabit,  but  as  it  is  exactly  fitted 
to  their  size,  it  cannot  be  easily  imagined  that 
the  animal  could  perform  this  motion  within  it. 
Another  circumstance  opposed  to  this  opinion 

*  Rotatory,  like  a  wheel,  from  the  Latin  rota,  a  wheel. 


is,  that  the  mollusks  whose  shells  are  per- 
fectly smooth,  are  capable  of  producing  the 
same  excavation  as  those  which  have  a  surface 
as  rough  as  a  file.  Many  have  supposed  that 
these  animals  possess  some  liquid  which  acts  as 
a  solvent  upon  the  substance  they  enter.  This 
appears  the  more  probable,  as  they  are  known  to 
emit  a  phosphorescent  light. 

The  entrance  is  the  smallest  part  of  the  dwell- 
ing of  the  Pholades,  and  hence  it  is  evident 
that  they  must  have  penetrated  the  rock  when 
young  and  small,  and  enlarged  their  perforations 
as  they  themselves  increased  in  dimensions.  The 
position  of  the  hole  is  always  oblique  to  the 
horizon  :  its  form  that  of  a  truncated  cone, 
terminated  by  a  rounded  cavity.  This  cavity 
receives  the  body,  while  the  farthest  end  is 
occupied  by  the  proboscis,  which  is  continually 
protruded  to  the  orifice  to  procure  the  sea  water, 
upon  which  it  subsists.  The  proboscis  is  long, 
pliable,  and  fleshy,  terminated  by  a  corneous 
substance,  which  is  dentated  like  a  saw  at  its 
extremity.  There  is  an  opening  between  the 
valves,  through  which  it  is  projected,  and  a  case 
into  which  it  fits.  At  the  approach  of  danger, 
these  mollusks,  by  means  of  this  instrument 
eject  water  to  a  considerable  height,  and  its 
dentated  margin  leads  us  to  suppose,  that  they 
also  employ  it  in  the  work  of  perforation. 

PHOLAS  Candida* 


Specific  Character.  Shell  oval,  obtuse,  nearly 
closed  at  the  anterior  end,  thin,  fragile,  almost 
transparent,  striated  transversely,  and  crossed 
by  finer  striae  in  a  radiated  form  from  the  um- 
bones,  a  few  of  the  radii  at  the  larger  end  set 
with  short  spines ;  hinge  smooth  and  reflected, 
teeth  slender  and  curved ;  one  valve  has  a 
curved  lamina  above  the  tooth  ;  there  is  a  single 
accessory  valve  ;  the  colour  is  yellowish  white  ; 
it  is  about  three  quarters  of  an  inch  long,  and 
three  inches  broad. 

These  Pholades  inhabit  marine  rocks  ;  they 
are  found  in  great  numbers  on  the  Devonshire 
coast ;  the  stone  in  which  they  are  imbedded  is 
a  cementation  of  the  finest  sand  and  limestone ; 
it  is  very  soft  when  first  taken  from  the  bed, 
and  so  absorbent  as  to  afford  sufficient  moisture 
for  the  purposes  of  life,  and  for  the  peculiar 
actions  of  the  mollusk.  The  animal  secretes  a 
mild  phosphorescent  solution,  which  would  be 
of  sufficient  power  to  decompose  the  rock  by 
the  contact  of  its  gradually  increasing  bulk. 

*  Plate  X.  figure  8. 

Genus— CHITON.*— (Plural,  Ckitones.) 


Generic  Character.  Shell  multi valve,  com- 
posed of  eight  valves,  rarely  of  seven  or  six ; 
form  convex  oval ;  the  valves  are  arranged  in  an 
imbricated  manner,  the  margin  of  one  being  in- 
cumbent on  that  of  the  next ;  they  are  surrounded 
and  connected  by  an  elastic  coriaceous  mem- 
brane, which  allows  of  the  free  movement  of  the 
valves,  it  is  either  scaly,  hairy,  or  spinous. 


The  Chitons  are  readily  distinguished  from  all 
other  testaceous  mollusca  by  the  form  of  their 
shell,  which  very  much  resembles  a  small  vessel 
or  boat  turned  upside  down,  and  by  the  peculiar 
arrangement  of  its  moveable  valves  attached  by 
a  coriaceous  membrane.  This  latter  substance 
is  capable  of  sufficient  expansion  and  contraction 
to  admit  of  considerable  play  in  the  valves,  so 
that  the  animal  can  roll  up  its  shell  into  the 
form  of  a  ball,  having  all  the  appearance  of  a 
wood-louse.  Thus  covered  by  its  scales  it  lies 
like  a  pebble  at  the  bottom  of  the  sea,  and  so 

*  Plate  X.  figure  5. 


contrives  frequently  to  escape  the  vigilance  of 
its  enemies.  The  mollusks  of  the  Chitons  are  of 
the  same  form  as  their  shells,  the  plates  of  which 
are  fixed  in  the  mantle  ;  the  gills  surround  their 
bodies  ;  they  breathe  only  water,  and  have  a 
fleshy  foot,  upon  which  they  creep.  Their  abode 
is  in  the  sea  at  an  inconsiderable  depth  near  the 
shore.  They  fix  themselves  for  a  time  to  rocks 
and  stones,  but  they  can  remove  at  pleasure. 
The  situation  and  formation  of  the  valves  resem- 
ble the  plates  which  constitute  a  suit  of  armour, 
or  coat  of  mail ;  and  to  this  resemblance  the 
shell  owes  its  name,  which  is  derived  from  %ITM, 
(chiton)  a  coat  of  mail. 

CHITON  Fascicularis. 


Specific  Character.  Shell  with  eight  valves, 
apparently  smooth,  but  when  viewed  through  a 
glass,  found  to  be  rough  like  shagreen,  except 
on  the  elevated  dorsal  ridge  ;  the  margin  is  sur- 
rounded with  tufts  of  whitish  hairs  at  the  junc- 
tion of  each  valve,  there  are  also  two  tufts  in 
front,  making  altogether  eighteen.  The  colour 
is  brown  or  dark  grey,  often  mottled  ;  the  length 
is  rather  less  than  an  inch. 

The  animal  of  this  Chiton  adheres  to  oysters 
and  other  shells,  and  with  them  inhabits  the 
deep  :  it  is  also  found  on  stones.  It  is  not  un- 
common on  the  coast  of  Devonshire ;  on  those 
of  Barbary  it  occurs  of  a  much  larger  size. 


CHITON  Squamosus* 


Specific  Character.  Shell  with  eight  valves, 
one  half  of  each  valve  is  striated  longitudinally, 
and  the  other  half  transversely  ;  the  margin 
scaly  ;  the  outside  is  dark  brown,  more  or  less 
variegated  with  olive,  and  the  inside  is  light 
bluish  green  ;  the  margin  is  beautifully  che- 
quered with  light  green  and  dark  olive  scales. 

Inhabits  the  coasts  of  America. 

Genus— LEPAS,f  (Plural,  Lepades.) 


Generic  Character.  Shell  multivalve,  more 
or  less  of  a  conical  form,  either  affixed  by  their 
base,  or  by  a  peduncle  ;  valves  erect,  oval,  une- 
qual, varying  in  number,  most  frequently  six. 


This  genus  consists  of  two  principal  divisions ; 
the  shells  contained  in  the  one  are  sessile,  or 
affixed  at  their  base,  those  of  the  other  are 
peduncled.  •'•  «.fy  "I 

*  Plate  X.  figure  5.  t  Plate  X.  figures  6,  7. 


Though  dissimilar  in  their  appearance,  these 
shells  are  united  by  many  points  of  resemblance ; 
they  are  all  more  or  less  of  a  conical  form,  com- 
posed of  several  valves,  and  are  parasitical.  The 
animals  inhabiting  them  are  very  similar,  and 
differ  much  from  other  mollusks.  They  have 
no  head  or  eyes,  the  mouth  has  jaws,  with  horny 
laminae  or  erect  teeth  ;  but  the  most  singular 
part  of  their  structure  consists  in  the  numerous 
tentacular,  curled,  articulated  arms;  these  vary 
in  number,  some  of  the  species  have  as  many  as 
twenty-four.  They  are  arranged  in  pairs,  and 
are  all  inserted  together  ;  the  twelve  longest  are 
erect  and  arched,  appearing  like  curled  feathers  ; 
they  are  clear  and  horny  ;  each  joint  is  furnished 
with  two  rows  of  hair  on  the  concave  side.  The 
animals  make  use  of  these  organs  to  catch  their 
prey,  and  are  continually  extending  and  con- 
tracting them.  The  twelve  smallest  are  placed 
in  front,  they  are  more  flexible,  and  more  thickly 
set  with  hairs  than  the  others. 

The  sessile  shells  *  are  now  formed  into  a  dis- 
tinct genus  called  Balanus:  they  adhere  imme- 
diately to  marine  substances  at  their  base,  and 
remain  immoveably  fixed  for  life  ;  the  form  of 
the  shell  is  conical,  and  the  valves  of  which  it 
is  composed,  are  so  strongly  cemented  as  almost 
to  appear  like  a  single  piece.  From  the  con- 
struction of  the  shell,  its  immoyeable  walls,  and 
its  large  opening  at  the  apex,  the  animal  would 
be  in  a  very  exposed  and  perilous  situation, 

*  Plate  X.  figure  6. 


had  not  the  compensatory  providence  of  the 
Creator  been  exerted  in  affording  it  a  safeguard. 
This  consists  of  a  very  efficient  operculum,  com- 
posed of  four  testaceous  pieces,  moveable  at 
pleasure,  and  articulating  with  the  sides  of  the 
shell,  sometimes  near  the  base,  sometimes  to- 
wards the  middle.  The  union  of  these  valves 
forms  a  pointed  cone,  which  completely  covers 
the  opening  at  the  apex,  and  protects  the  mol- 
lusk,  who  can  open  it  at  pleasure  to  put  out  its 
arms,  and  draw  in  food.  The  increase  in  the 
height  of  these  shells  is  clearly  indicated  on 
their  lateral  valves,  whilst  at  the  base  are  traces 
of  extension  in  width  ;  it  is  probable  that  at 
each  period  of  growth,  the  animal  disunites  its 
valves  and  connects  them  again,  having  added 
the  necessary  portion  to  their  size. 

The  Linnaean  name  of  Lepas  is  now  confined 
to  the  division  containing  the  Peduncled  shells.* 
The  mollusk  inhabiting  them  may  be  considered 
as  different  from  those  of  the  Balanus,  because  the 
tube  which  supports  the  shell  is  in  fact  a  part 
of  the  animal :  it  is  organized,  living,  and  fur- 
nished with  muscles  which  give  the  Lepas  the 
power  of  regulating  its  movements.  The  shell 
is  composed  of  five  valves,  two  on  each  side, 
and  one  long  and  narrow  on  the  dorsal  ridge ; 
these  valves  are  united  by  a  membrane  ;  the  form 
of  the  ^shell  is  that  of  a  flattened  cone  ;  the  base 
is  sustained  by  the  tubular  flexible  peduncle,  by 
which  the  shell  is  attached  to  marine  substances. 

*  Plate  X.  figure  7. 


LEPAS  Tintinndbulum* 


Specific  Character.  Shell  sessile,  the  valves 
irregularly  and  strongly  ribbed  longitudinally, 
and  the  interstices  delicately  striated  trans- 
versely; the  form  is  sometimes  conical,  some- 
times cylindrical ;  the  colour  is  pinkish  inclining 
to  purple  ;  the  diameter,  which  is  sometimes 
exceeded  by  the  height,  varies  from  half  an  inch 
to  two  inches. 

This  shell  is  found  in  the  West  Indies,  and 
coasts  of  Africa,  and  often  on  the  bottom  of 
ships  arriving  from  more  southern  latitudes; 
but  its  claim  to  be  considered  as  a  native  of 
Britain  is  very  doubtful* 

LEPAS  Anatifem.^ 


Specific  Character.  Shell  compressed,  some- 
what triangular,  composed  of  five  valves  ; 
the  two  lower  ones  are  large,  triangular,  and 
faintly  striated ;  the  two  superior  valves  long 
and  tapering  downwards  to  an  obtuse  point,  the 
upper  part  angular  on  each  side,  the  top  roun- 
ded ;  these  valves  are  also  slightly  striated  ;  the 
dorsal  valve  is  long,  slender  and  rounded ;  the 
*  Plate  X.  figure  6.  f  Plate  X.  figure  7. 


cartilages  that  connect  the  valves  and  the 
peduncle  are  usually  of  a  reddish  orange  colour  ; 
the  valves  are  blueish  white  ;  the  length  is  about 
an  inch  and  a  half,  the  breadth  of  the  largest 
part  is  an  inch;  the  peduncle  is  sometimes  a 
foot  long. 

This  species  is  found  in  all  parts  of  the  world, 
adhering  in  great  quantities  to  the  bottom  of 
ships.  It  attaches  itself  particularly  to  wood  : 
sometimes  pieces  of  timber  are  thrown  on  shore 
completely  covered  with  it.  A  most  strange 
idea  formerly  prevailed,  that  the  Barnacle  goose 
was  produced  from  these  shells. 


1.  How  is  the  generic  character  of  Multi- 
valve  shells  determined  ? 

2.  What  is  the  generic  character  of  the  Pholas  ? 

3.  Why  is  the  Pholas  now  generally  consi- 
dered as  a  Bivalve  shell  ? 

4.  What  are  the  habits  of  the  Pholades  ? 

5.  How  is  the  Phoias  supposed  to  perforate 
the  different  substances  it  inhabits  ? 

6.  What    is    the    generic   character   of    the 
Chiton  ? 

7.  Describe  the  habits  of  the  Chiton. 



8.  What  is  the  generic  character  of  the  Lepas  ? 

9.  Describe  the  two  families  into  which  the 
Lepas  is  divided. 

10.  Describe  the  animal  which  inhabits  the 
L  epas. 


Testaceous  bodies  are  not  only  to  be  admired 
for  their  beauty,  but  valued  for  their  usefulness. 
Several  of  their  animals  afford  a  very  nutritious 
diet.  The  oyster  supplies  the  table  of  the  rich 
with  a  wholesome  delicacy  ;  in  many  maritime 
situations  the  poor  population  are  almost  entirely 
supported  by  various  shell  fish,  as  muscles, 
cockles,  pectens,  solens,  &c.  The  medicinal 
qualities  of  the  snail  have  rendered  it  a  suitable 
sustenance  for  the  invalid.  Mollusks  not  only 
contribute  to  supply  the  wants  of  man,  but  they 
form  the  subsistence  of  other  animals ;  they  are 
the  prey  of  various  fishes,  and  are  a  favourite  food 
of  seafowl,  who  exert  much  ingenuity  in  getting 
at  them  :  when  they  find  their  beaks  insufficient 
to  pierce  a  shell,  they  will  ascend  with  it  to 
some  neighbouring  eminence,  from  whence  they 
drop  it,  that  it  may  be  crushed  against  the 
rocks.  The  monkey  also  regales  himself  with 
shellfish ;  at  the  reflux  of  the  tide,  when  the 


Mollusks  for  want  of  water,  keep  their  shells 
open,  he  stations  himself  on  the  sea  shore,  aware 
of  the  danger  of  inserting  his  paws  between  the 
valves,  he  drops  in  a  stone  or  two,  by  which 
he  prevents  their  closing,  and  is  enabled  to 
extract  his  prey  with  impunity.  The  shells 
also  of  Testaceous  animals  are  useful  in  various 
ways.  In  America  the  greatest  quantity  of 
the  lime  used  for  agricultural  and  architectural 
purposes  is  made  of  calcined  shells.  The  public 
streets  of  Christianstadt  and  Santa  Cruz  are 
paved  with  the  Strombus  Gigas. 

In  uncivilized  countries  the  natives  not  only 
delight  to  deck  their  persons  with  shells,  but 
where  the  working  of  iron  is  still  unknown, 
they  often  employ  shells  as  its  substitute,  and 
convert  them  into  agricultural  or  domestic  im- 
plements, and  also  warlike  instruments.  The 
military  horn  of  many  of  the  African  tribes  is 
formed  of  the  Murex  Tritonis.  The  blue  and 
white  belts  of  the  Indians  of  North  America, 
used  as  symbols  of  peace  and  amity,  in  oppo- 
sition to  the  war  hatchet,  is  made  from  the  Venus 
Mercenaria ;  and  the  gorget  of  the  chieftain's 
dress,  is  constructed  of  the  Mytilus  Margarati- 
ferus.  Among  the  Friendly  Isles  the  permission 
to  wear  the  Cyprsea  Aurantia  or  Orange  Cowry 
marks  the  highest  rank  of  the  country.  The 
Cypraea  Moneta  or  Money  Cowry  is  the  current 
money  of  many  nations  of  India  and  Africa, 
and  the  liberty  of  a  man  is  often  bartered  for* 
a  certain  weight  of  these  shells.  In  Grecian 
p  2 


History  we  read  that  the  suffrages  of  the 
Athenians  were  on  certain  occasions  marked 
upon  a  shell.  Pearls,  the  effect  of  disease  in 
certain  Mollusca,  form  a  portion  of  the  revenue 
of  many  kingdoms,  and  are  among  the  most 
costly  ornaments  of  the  noble  and  the  wealthy. 
In  former  times  the  dye  extracted  from  the  Pur- 
pura  was  a  most  valuable  article  of  commerce, 
but  it  has  now  been  superseded  by  that  which 
the  Cochineal  furnishes  in  so  much  greater 





















My  til  us. 























































LIN.                         LAM. 

Chiton,  l 

VII.  Cardium.         -{  Cardium.9 


f  Lutraria. 


nearly  all. 




VIII.  Mactra.         -(  Crassatella. 




,  -  -  .  •            i 



part.  , 






f  Pholas.4 
[  Gastrochsena. 






r  Petricola. 














X.  Venus. 

Lucina.     part 
Donax.     part. 

,  Solen.6 
I  Anatina.  part. 
i  Sanguinolaria. 

Cyrena.   part* 

'Mya.    part. 



XI.  Spondylus.       J  s^onxMus3" 





*  Psammotxa. 



VTI    nv.««                  Isocardia.15 
XII.  Chama.           J  chama 


1  Tridacna. 



1  Plate  10.  fig.  5. 
5  Plate  10.  fig.  7.  8. 
9  Plate  8.  fig.  1,  2. 
13  Plate  8.  fig.  9. 

2  Plate  10.  fig.  6.  3  Plate  10.  fig.  7,  4  Plate  10.  fig.  8. 

6  Plate  7.  fi-s  3.  4.  7  Plate  7.  fig.  6,  8.9-  8  Plate 7.  fig.  7- 

10  Plate  8.  fig.  3, 4,  9.  11  Plate  8.   fig.  5,  6.  12  Plate  8.  fig.  7. 

14  Plate  8.  fig  10.  15  Plate  9.  fig.   3.  16  Plate  9.  fig.  2 . 




LAM.                             LIN                            LAM. 

Bull  sea. 



XIII.  Area. 

I  Pectunculus.  1 
]  Area.  2 

Bulla.  «3 


1  Cucullaea. 

XXII.  Bulla. 



Physa.14   part. 

:     «        .I'!-; 



'  Cucullsea. 

f  Auricula. 

XIV.  Ostrea. 

-  Pedum 

1  Ancilla. 
j  Cancellaria. 


XXIII.  Voluta. 

Mitra.  16 

•  '-'Strea. 





1  Anomia.5 

^Oliva.i7       -9 

XV.  Anomia. 

j  Crania. 
1  Orbicula. 


j  Terebratula.  6 











XVI.  Mytilus. 


Pyrula.     part. 


XXIV.  Buccinum.  • 

Mnrex.      part 

Ostrea.     some* 



XVII.  Pinna, 

-{  Pinna. 





(  Argonauta.  9 
XVIII.  Argonauta.  j  Carinaria. 

Dolium.  V 


XIX.  Nautilus. 

/  Nodosaria. 
1  Spirula. 
1  Cristellaria. 

/•  Pirena. 

XXV.  Strombus.     . 


XX.  Conus. 

•{  Conus.n 



XXI.  Cypraea. 

-{  Cypraea.i2 

„  Purpura. 

1  Plate  9.  fig.  5. 

2  Plate     fie.  6.               3  Plate  9.  fig  8.                     4  Plate  9.  fig.  7, 

5  Plate  10.  fig.  1. 
9  Plate  6.  fig.  5. 

6  Plate  9.  fig.  9.             7  Plate  10.  fig.  2.                  8  Plate  10.  fig.  3. 
10  Plate6.fig.  4.             11   Plate  2.  fig.  1.                     12  Plate2.fig.  a,  4,  5. 

13  Plate  2.  fig.  6. 

14  Plate  2.  fig.  9.              15  Plate  2.  fig.  8                      16  Plate  2.  ft.  ll. 

17  Plate2.  fig.  10. 

18  Plate  3.  fig.  3,            19  Plate  3.  fig.  2.                  20  Plate  3.  fig.  1. 
21  PlateS.  fig.  4.             22  Plate3.fig.6. 


XXVI.  Murex. 

XXVII.  Trochus. 

XXVIII.  Turbo. 

XXIX.  Helix. 

1  Plate  3- fig.  2. 
5  Plate  6.  fig.5. 
9  Plate  4.  fig.  3. 
13  Plate  5.  fig.  8. 

17  Pla 

INN^EAN  GENERA  OF  SHELLS.                   217 


LIN.                            LAM. 


Planorbis.  s 







1  Fasciolaria. 

Paludina.  part. 

|  Fusus. 


J  Pyrula. 




Ranella.l             < 




Triton.  3 



r  Navicella. 


XXX.  Nerita.          \  Nerita"*' 

Pyramidella.  4 

I  Natica. 

Solarium.  5 


(  Stomatia. 
XXXI.  Haliotis.      \  Haliotis.i* 




r  Lingula. 


XXXII.  PateUa.      \  FissureUa.'3 
Crepidula.  , 

Trochus.  part. 



XXXIII.  Dentalium.     Dentalium.ic 




'Helix.  7 





IrS^Sum  i7 



Pupa.    some. 



(^Vermetus.  is 




XXXV.  Teredo.       J  Septaria.  part 

Plate  4.  fig.  1.                3  Plate  4.  fig.  3.           4  Plate  4.  fig.  6. 
,  Plate  4.  fig.  78.            7  Plate  4.  fig.  1.           8  Plate  4.  fig  2. 
Plate  5!  fig.5.  '               11  Plate5.  fig.  4.         12  Plate  5.  fig.  6. 
Plate  6.  fif.  1.                15  Plate       5.  fig.  4.  16  Plate  6.  fig.  6. 



Acephala.  Without  a  head  from  the  Greek 
K€<paXv)  (cephale)  a  head. 

Apex.     In  univalve  shells,  the  top  of  the  spire. 

Apices.  The  plural  of  apex.  In  bivalve  shells, 
the  points  over  the  hinge  :  called  also 
the  Beaks.  ; 

Aperture.    The  entrance  or  opening  of  the  shell. 

Auricula.  Small  earlike  appendages  placed  at 
the  sides  of  the  hinge  of  some  bivalve 
shells  :  the  diminutive  of  auris,  an  ear. 

Area,  or  Anterior  slope.  The  side  of  the  beaks 
where  the  ligament  is  situated. 

Areola,  or  Posterior  slope.  The  side  of  the 
beaks  opposite  to  that  where  the  liga- 
ment is  placed. 

Articulated.  Having  joints ;  from  articul  us,  a 

Annulated.  Marked  with  rings  ;  from  annul  us. 
a  ring. 

Alatce.     Winged  ;   from  ala,  a  wing. 

Adductor  Muscle.  The  muscle  that  closes  the 
valves  ;  from  adduce,  I  bring  together. 

Base.     In  univalve  shells,  the  extremity  oppo- 


site  to  the  apex.     In  bivalve  shells  that 

part  of  the  margin  which  is  opposite  to 

the  beaks. 
Bivalve.     A  shell  with  two  valves;  from  bis, 

twice,  and  valve. 
Bifid.     Cleft  in  two  ;  from  bis,  twice,  and  fid  i, 

I  have  cleft. 
Bifurcated.     Having  a  fork  of  two  teeth  ;  from 

bis,  twice,  and  furc  a,  a  fork. 
Branchiae.     Gills;    from   the   Greek    /-fyayxta, 

(branchia)  the  gills  of  fish. 
Cardo  or  Hinge.     In  bivalves,  that  part  of  the 

circumference  where  the  valves  cohere. 
Carinate.     Furnished  with  a  keel-like  elevated 

ridge;  from  carina,  a  keel. 
Columella.      The  pillar  round  which  the  whorls 

form  their  spiral  circuit;  from  columella, 

a  little  column.        ;* 
Convoluted.     Rolling  regularly  over  each  other ; 

from  con,  together ;  and  volut  us,  rolled. 
Cephalopodes.     Having  feet  on  the  head  ;  from 

the  Greek  /ce^aX^,   (cephale)  a  head,  and 

7ro&€$,  (podes)  feet. 
Cephala.     Having  a  head ;    from    the    Greek 

K€<pahy  (cephale)  a  head. 
Corneous.     Horny ;  from  cornu,  a  horn. 
Crenated.     Notched ;  from  cren  a,  the  notch  of 

an  arrow. 
Coriaceous.     Like  leather ;  from  cori  um,  skin, 

Callosity.     Hardness    of   skin  or    flesh ;    from 

call  us,  which  has  the  same  signification. 


Ciliated.  Furnished  with  a  fringe  like  eye- 
lashes ;  from  cilia,  an  eyelash. 

Cordate.  Heart-shaped ;  from  the  Latin  (cor) 
a  heart. 

Contracted.  The  mouth  is  called  contracted, 
when  the  lips  are  not  separated  by  any 
channel  or  sinus  ;  it  then  holds  liquids 
though  filled  up  to  the  brim. 

Congener.  One  of  the  same  genus  ;  from  con, 
together  and  genus,  a  kind. 

Coronated.     Crowned  or  girt  towards  the  apex. 

Cancellated.  Crossed  like  the  bars  of  a  latticed 
window  ;  from  cancelli,  lattice. 

Complicated.  Folded  together;  from  con,  with, 
together,  and  plicare,  to  fold. 

Digitations  or  Claws.  Finger-like  lobes ;  from 
digitws,  a  finger. 

Dextral.  Righthanded,  turning  round  the  pil- 
lar from  left  to  right,  the  usual  course  of 
the  whorls ;  from  dextra,  the  right  hand. 

Dorsal.  Belonging  to  the  back  ;  from  dorszm, 
the  back. 

Deciduous.  Falling,  not  lasting  ;  from  decido, 
I  fall. 

Dentated.     Toothed  ;  from  dens,  a  tooth. 

Diaphanous.  Capable  of  transmitting  light, 
transparent;  from  the  Greek  &a  (dia) 
through,  and  paivu  (phaino)  I  appear. 

Decorticated.  Having  the  bark  or  outer  skin 
taken  off ;  from  de,  off,  and  cortex,  bark. 

Dissepiment.  A  division  between  two  chambers 
in  a  shell ;  from  sepes,  a  hedge,  and  dis, 


a  prefex,  signifying  division. 
Decussated.     Crossed  like  an  X  ;  from  decussis, 

the  mark  X  (ten). 
Disk.     The  convex  part  of  the  valves  between 

the  urn  bones  and  the  margin,  applied  also 

to  any  extended  or  rounded  surface  ;  as  in 

Haliotis,  from  the  Latin  discus,  a  dish 

or  platter. 
Effuse.     Having  the  lips  separated  by   a  sinus 

or  gutter,  so  that  if  the  shell  were  filled 

with  water,  it  would  flow  out  at  the  sinus 

before  it  reached  the  margin ;  from  fus  us, 

poured  out. 
Epidermis.     The    membranaceous   covering    of 

some  species  of  shells  ;    from  the  Greek 

em  (epi)  upon,  and  $ep/xa  (derma)  a  skin. 
Eroded.     Gnawed  out,  from  the  Latin  e,  out, 

and  rod  ere,  to  gnaw. 
Entire.     The  mouth  is  said  to  be  entire,  when 

the  lips  are  not  separated  by  a  canal. 
Equivalve.     Having  equal  valves  ;  from  equ  us 

equal,  and  valve. 
Equilateral.     Having  both  sides  equal  ;  from 

equ  us,  equal,  and  latera,  sides. 
Emarginated.     Notched,  or  having  the  margin 

excavated  by  a  sinus. 
Ferruginous.     The  colour  of  rust  or  iron-mould ; 

from  ferrugo,  iron  rust. 

Flexuous.     Winding  full  of  turns  and  meanders. 
Fusiform.     Shaped  like  a  spindle;  swollen  in 

the  middle,   and  tapering  to  each  end; 

from  fusis,  a  spindle. 


Fluviatile.     Belonging    to    fresh    water;   from 

fluviws,  a  river. 
Globose,  Globular.     Approaching  the  form  of  a 

Genus.     A  separate  family,   distinguished  from 

all  others  by  certain  permanent  marks, 

called  generic  characters  ;  from  gen  us,  a 

Gibbous.     Convex,  swelling  out,  from    gibbus, 

a  swelling,  a  hunch  on  the  back. 
Gaping.     The  valves  so  partially  closing,   that 

the  margins  do  not  touch  at  every  part  of 

the  circumference. 
Imbricated.     Lying   one  over   another   like  the 

tiles  of  a  house  ;  from  imbrex,  a  tile. 
Iridescent.     Displaying   the   varied    colours   of 

the  rainbow ;    from  iridescere,   to   shine 

like  a  rainbow,  in  Latin  iris. 
Insterstice.  Space  between  one  part  and  another. 
Inequivalve.     Having  unequal  valves  ;  from  in, 

not,  equ  us,  equal,  and  valve. 
Inequilateral.     Having     sides     not     uniform ; 

from  in,  not,  equ  us,  equal,  and  latera, 

Involuted.     Rolled  inwards ;   from  involut  us, 

rolled  up  in. 
Littoral.     Belonging  to  the  shore ;  from  litt  us, 

a  shore. 

Lateral.     At  the  sides  ;  from  later  a,  sides. 
Longitudinal.     In  the  direction  of  the  length  of 

a  shell;    (  i.  e.  )   from  the  apex  to  the 



Laminated.  Having  thin  layers  or  scales  called 

Linear.  Having  the  character  of  a  line  ;  ex- 
tremely narrow  in  proportion  to  its 
breadth,  and  of  nearly  equal  diameter 

Length.  In  Bivalves,  the  dimension  extending 
from  the  hinge  to  the  opposite  margin ; 
in  Univalves,  that  from  the  apex  to  the 

Ligament.  A  cartilage  which  connects  the 
valves ;  from  lig  are,  to  bind. 

Lanceolate.     Shaped  like  the  head  of  a  lance. 

Lips.  The  margins  of  the  mouth  of  a  univalve 
shell.  The  columellar  lip  is  the  margin 
nearest  the  columella.  The  outer  Up  is 
the  outer  margin  of  the  aperture. 

Locomotion.  The  power  of  moving  voluntarily 
from  place  to  place ;  from  loc  us,  place, 
and  motion. 

Lubricated.  Slippery ;  having  a  very  smooth 
surface ;  from  lubric  us,  slippery. 

Multivalve.  Having  several  valves,  from 
mult  us,  many. 

Mollusca.  The  animals  inhabiting  shells ;  the 
name  is  derived  from  mollis,  soft.  They 
are  divided  into  two  classes  :  those  which 
have  a  head  called  Mollusca  Cephala, 
from  the  Greek  ice^aX^,  (cephale)  a  head  ; 
and  those  without  a  head  Mollusca  ace- 
phala,  from  the  Greek  a  (a)  without,  and 


Muricated.  Having  little  pointed  knobs ;  from 
murex,  the  sharp  point  of  a  rock. 

Marine.  Belonging  to  the  sea ;  from  mare,  the 

Multilocular.  Having  several  chambers,  from 
mult  us  many,  and  locul  um,  a  little 

Operculum  or  Lid.  A  plate  or  door,  with  which 
some  species  close  the  aperture  of  their 
shells,  from  oper  iort  I  cover. 

Orbicular.     Quite  round,  or  circular. 

Parallel.  Running  in  the  same  direction  as 
another  thing,  being  always  at  the  same 
distance  from  it;  from  the  Greek  napa 
(para)  by  the  side  of,  and  aXT^A  wv  (alle- 
lon)  each  other. 

Pellucid.  So  clear  that  the  light  is  seen  through  ; 
from  per,  through,  and  lua?,  light. 

Pervious.  Easily  passed  through ;  from  per, 
through,  and  via  a  way. 

Plicated.  Folded  or  plaited ;  from  plica,  a 

Punctured.  Pricked  or  marked  with  small 
dots  ;  from  punct  um,  a  point  or  dot. 

Patulous,  lying  open  or  spreading ;  from  pat  er€t 
to  lye  open. 

Quincunx.  Disposed  alternately  as  in  rows  of 
spots,  when  the  spots  of  each  row  are 
opposite  to  the  space  between  two  spots 
of  the  next  row  ;  from  quin^we,  five,  and 
unx,  ounce,  as  the  weight  representing 
five  ounces  was  stamped  thus  :•: 


Rotatory.     Like  a  wheel;  from  rota,  awheel. 

Rostrated.  Having  a  beak  from  rostrwra,  a 

Refuse.  Having  the  lower  whorls  of  the  spire 
pressed  into  the  body  whorl,  from  re- 
back,  and  tusws,  beaten. 

Reversed.  Applied  to  spiral  shells,  whose  volu- 
tions turn  in  the  contrary  direction  to 
the  generality  of  shells,  If  when  a  shell  is 
placed  on  its  base,  with  the  front  facing 
the  person  looking  at  it,  the  aperture  is 
on  the  right  side  of  the  pillar,  the  shell  is 
said  to  be  regular  or  dextral,  if  the  aper- 
ture is  on  the  left  side  of  the  pillar,  it  is 
said  to  be  reversed  or  sinistral. 

Retractile.  Capable  of  being  drawn  back ;  from 
re,  back,  and  tract  us,  drawn. 

Reticulated.  Crossed  like  net  work  ;  from  reti- 
culww,  a  small  net. 

Revolute.  Rolled  back ;  from  re,  back,  and 
volutws,  rolled. 

Rugose.  Rough  or  wrinkled ;  from  ruga,  a 

Rufous.     Of  a  reddish  colour. 

Spire.  The  upper  whorls  collectively  ,  from 
the  Greek  a-ireip  (speir),  convolutions 
gradually  increasing  in  diameter. 

Suture.  The  circular  line  of  the  spire,  where 
one  volution  meets  another  ;  from  sutura, 
a  seam. 

Species.  The  subdivision  of  a  genus,  and  dis- 
tinguished from  all  others  of  the  genus 


by     permanent     marks     called    specific 

Striated.  Marked  with  fine  striae,  or  lines, 
either  hollow  or  raised ;  from  stria,  a 

Sinus.  A  gutter,  or  curvature  ;  from  sinws,  a 
curved  line. 

Sinuous.     Having  a  curvature. 

Subulate.  Tapering,  or  pointed ;  from  subula, 
a  pointed  tool. 

Sagittate.    Arrow-like  ;  from  sagitta,  an  arrow. 

Siphon.  A  pipe  through  which  liquids  are 

Sub.  In  composition  means  almost,  or  ap- 
proaching to. 

Setaceous.     Bristle  shaped ;  from  seta,  a  bristle. 

Semi.     Half. 

Sinistral.  On  the  left  hand  ;  from  sinistra,  the 
left  hand. 

Sides.  The  right  side  of  a  univalve  is  that 
opposite  the  right  hand  of  the  person 
looking  at  it,  when  the  shell  is  placed  on 
its  base  with  the  aperture  in  front :  the 
left  side  is  that  opposite  the  left  hand, 
the  shell  being  in  the  same  position. 

Terrestrial.  Belonging  to  the  earth  ;  from 
terra,  earth. 

Testaceous.  Composed  of  the  materials  which 
form  shells ;  from  the  Latin  testa,  a 

Tentacula.  The  feelers  of  the  mollusca  ;  from 
the  Latin  ten  to,  I  try. 


Turbinate.  The  body  swelling,  and  spire  com- 
paratively small ;  from  the  Latin  tur- 
bin  is,  of  a  whirlwind. 

Turreted.  The  whorls  gradually  decreasing  to 
a  fine  point ;  the  length  of  turreted  shells 
greatly  exceeds  their  breadth. 

Turgid.     Swollen,  puffed  up. 

Teeth.  The  pointed  protuberances  at  the  hinge 
of  bivalve  shells;  the  cardinal  or  central 
teeth  are  those  situated  on  the  hinge  ; 
the  Lateral  teeth  are  those  at  the  sides 
of  the  hinge,  and  are  often  remote. 

Tuberculated.  Covered  with  tubercles,  or  small 

Tortuous.  Twisted;  from  the  Latin  tort  MS, 

Transverse.  Placed  across,  or  crossways. 

Truncated.  Cut  short  or  abruptly  off  at  the 

Umbones,  or  Bosses.  The  swelling  parts  of 
bivalve  shells  near  the  beaks  ;  from  umbo, 
the  boss  of  a  shield.  The  highest  points 
of  these  are  considered  the  summits. 

Umbilicus.  A  small  hollow  at  the  base  of  the 
columella,  visible  underneath. 

Undulating.  Wave-like  ;  from  undula,  a  little 

Univalve.  A  shell  composed  of  one  valve  ;  from 
unws,  one,  and  valve. 

Volution  or  Whorls.  The  distinct  turns  of 
the  spire. 

Varices.  Longitudinal  gibbous  sutures  formed 
Q  2 


in   the  growth    of    the   shell  at   certain 

distances  on  the  whorl  ;  from  varix,  a 

swollen  vein. 
Vermiform.     Resembling    a    worm ;    from    the 

Latin  vermes,    a  worm  ;    and  forma,   a 

Ventricose.     Inflated.     Swelled  in  the  middle. 






Body  whorl. 



Area  or  Anterior 
Areola  or  Posterior 








Outer  lip. 
Columellar  lip. 



















Left  valve. 





Right  valve. 



1.  Conus  marmoreus. 

2.  Cyprsea  arabica     . 

3.  The  same^  young. 

4.  Cypraea  moneta 

5.  Cypraea  europcea    . 

6.  Bulla  lignaria  . 

7.  Gizzard  of  Ditto. 

8.  Bulla  volva.1     .     . 

9.  Bulla  fontinalis.2   . 

10.  Voluta  o&va.3    .     . 

11.  Voluta  episcopalis.* 

Marble  Cone. 
Nutmeg  Cowry. 

Money  Cowry. 
Nun  Cowry. 
Wood  Dipper. 

Weaver's  Shuttle. 
Stream  Dipper. 
Olive  Volute. 
Bishop's  Mitre. 

1  Ovula  Volva       of  Lamarck. 

2  Physa  Fontinalis         Ditto. 

3  Oliva  Ditto. 

4  Mitra  Episcopalis        Ditto. 



1.  Buccinum  dolium  l 

2.  Buccinum  harpa  2 

3.  Buccinum  flammeum  3 

4.  Buccinum  subulatum* 

5.  S  trombus  pes  pelicani 5 
(i.  The  same,  young  \    . 

Spotted  Tun. 
Harp  Shell. 
Triangular   Helmet. 
Tiger  Spire. 
Pelican's  Foot. 

1  Dolium  Maculatum         t)f  Lamarck. 

2  Harpa  Ventricosa  ditto, 
s  Cassis  Flammea  ditto. 
4  Terebra  Macidata  ditto. 
»  Rostellaria  Pes  Pelicani         ditto. 


1.  Murex  ramosus      .     . 

2.  Murex  rana1     .     .     . 

3.  Murex  maculosus 2 

4.  Trochus  zizyphinus     . 

5.  Trochus  perspectivus  3 

6.  Trochus  dolabratus 4   . 

7.  Turbo  scalaris5 

8.  Turbo  clathrus6     . 

Branched  Murex. 
Frog  Murex. 
Spotted  Murex. 
Livid  Top  Shell. 
Staircase  Shell. 
Zebra  Shell. 
Wentle  Trap. 
False  Wentle  Trap. 

1  Ranella  Crumersia        of  Lamarck. 

2  Triton  Maculosus  ditto. 

3  Solarium  Perspectwum,         ditto. 

4  Pyramidella  Dolabrata         ditto. 
f>  Scalaria  Pretiosa  ditto. 
6  Scalaria  Communis  ditto. 



Helix  pomatia    . 
Helix  cornea1 

.     Eatable  Snail. 
.     Horn  Snail. 



Helix  stagnalis  2 
Nerita  peloronta 
Nerita  corona3    . 

.     Lake  Snail. 
.     Bleeding  Tooth. 
Coronated  Nerite. 


Haliotis  tuberculata 

Common  Sea-ear. 


Patella  equestris*  . 
Patella  nodosa  5 

{Cup  and  Saucer 
Knotted  Limpet. 

i  Planorbis  corneous 
2  Hymnsea  stagnalis 
3  Neritina  corona 
4  Calyptraea  equqstris 
5  Fissurella  nodosa 

of  Lamarck, 


/  /  / 




1.  Patella  ungarica1 

2.  Serpula  lumbricalis  z 

3.  Serpula  aquaria3 

4.  Nautilus  Pompilius 

5.  Argonauta  argo    . 

6.  Dentalium  entails 

Hungarian  Bonnet. 

Cork  Screw  Shell. 

Watering  Pot. 
7  Large  Chambered 
)      Nautilus. 

Paper  Nautilus. 

Dog's  Tooth. 

1  Pileopsis  Ungarica  by  Lamarck. 
3  Vermetus  Lumbricalis  by    ditto 
3  Aspergellum  Javanum  by    ditto 




1.  Hinge  of  Mya. 

2.  Mya  truncata     .  .  Truncated  Gaper. 

3.  Hinge  of  Solen. 

4.  Solen  siliqua       .  .  Pod  Razor  Shell. 

5.  Solen  radiatus    .  .  Radiated  Solen. 

6.  Hinge  of  Tellina. 

7.  Tellina  carnaria  l  .  Rosy  Tellen. 

8.  Tellina  lingua  fells  .  Cat's  Tongue  Tellen. 

9.  Tellina    Madaqasca-  1  ».-    ,  ^  „ 

riensis.  }  Madagascar  Tellen. 

1  Lucnia  Carnaria  of  Lamarck. 




1.  Hinge  of  Cardium. 

2.  Cardium  edule 

3.  Hinge  of  Mactra. 


4.  Mactra  stultorum. 

5.  Hinge  of  Donax. 

6.  Donax  denticulata     . 

7.  Hinge  of  Venus. 

8.  Venus  dysera  .    ; .     • 
9*  Spondylus  gcedaropus 

10.  Spondylus  plicatula l 

Common  Cockle^ 

(  Simpleton's 

(  Kneading-trough. 

,     Toothed  Donax. 

Ribbed  Venus. 
Thorny  Oyster. 
Cat's  Paw. 

1  Plicatula  ramosa  of  Lamarck. 



1.  Hinge  of  Ohama. 

2.  Chama  hippopus  l 

3.  Chama  cor2  .     . 

4.  Hinge  of  Area. 

5.  Area  undata  3    . 

6.  Area  Noce     .. 

7.  Ostrea  violacea  4 

8.  Ostrea  malleus6  . 

Bear's  Paw  Clam. 
Heart  Clam. 

Lettered  Ark. 
Noah's  Ark. 
Violet  Scallop. 

1  Hippopus  maculatus    of  Lamarck 

2  Isocardia  cor  ditto. 

3  Pectunculus  undulatus        ditto. 

4  Pecten  violacea  ditto. 

5  Malleus  Vulgaris  ditto. 

6  Terebratula  psittacea          ditto. 



1.  Anomia  ephippium 

2.  My  til  us  edulis 

3.  Mytilus  margaritiferus } 

4.  Pinna  pectinata  .     .     . 
5^  Chiton  squamosus 

6.  Lepas  tintinnabulum  ~. 

7.  Lepas  anatifera  z 

8.  Pholas  Candida  .     .     . 

Wrinkled  Anomia. 

Common- Muscle. 

(  Muscle. 

Spiny  Sea  Wing.  • 

Scaly  Chiton. 



Duck  Barnacle, 
j  White  Stone- 
(     piercer. 

1  Meleagrina  tnargaratifera  of  Lamarck 

2  Balanus  tmtimmbulum  ditto. 

3  Anatifa  I  avis  ditto.